cmakecommands(1)cmakecommands(1)NAMEcmakecommands - Reference of available CMake commands.
COMMANDS
add_custom_command
Add a custom build rule to the generated build system.
There are two main signatures for add_custom_command The first
signature is for adding a custom command to produce an output.
add_custom_command(OUTPUT output1 [output2 ...]
COMMAND command1 [ARGS] [args1...]
[COMMAND command2 [ARGS] [args2...] ...]
[MAIN_DEPENDENCY depend]
[DEPENDS [depends...]]
[IMPLICIT_DEPENDS <lang1> depend1 ...]
[WORKING_DIRECTORY dir]
[COMMENT comment] [VERBATIM] [APPEND])
This defines a command to generate specified OUTPUT file(s). A
target created in the same directory (CMakeLists.txt file) that
specifies any output of the custom command as a source file is
given a rule to generate the file using the command at build
time. Do not list the output in more than one independent tar‐
get that may build in parallel or the two instances of the rule
may conflict (instead use add_custom_target to drive the command
and make the other targets depend on that one). If an output
name is a relative path it will be interpreted relative to the
build tree directory corresponding to the current source direc‐
tory. Note that MAIN_DEPENDENCY is completely optional and is
used as a suggestion to visual studio about where to hang the
custom command. In makefile terms this creates a new target in
the following form:
OUTPUT: MAIN_DEPENDENCY DEPENDS
COMMAND
If more than one command is specified they will be executed in
order. The optional ARGS argument is for backward compatibility
and will be ignored.
The second signature adds a custom command to a target such as a
library or executable. This is useful for performing an opera‐
tion before or after building the target. The command becomes
part of the target and will only execute when the target itself
is built. If the target is already built, the command will not
execute.
add_custom_command(TARGET target
PRE_BUILD | PRE_LINK | POST_BUILD
COMMAND command1 [ARGS] [args1...]
[COMMAND command2 [ARGS] [args2...] ...]
[WORKING_DIRECTORY dir]
[COMMENT comment] [VERBATIM])
This defines a new command that will be associated with building
the specified target. When the command will happen is determined
by which of the following is specified:
PRE_BUILD - run before all other dependencies
PRE_LINK - run after other dependencies
POST_BUILD - run after the target has been built
Note that the PRE_BUILD option is only supported on Visual Stu‐
dio 7 or later. For all other generators PRE_BUILD will be
treated as PRE_LINK.
If WORKING_DIRECTORY is specified the command will be executed
in the directory given. If it is a relative path it will be
interpreted relative to the build tree directory corresponding
to the current source directory. If COMMENT is set, the value
will be displayed as a message before the commands are executed
at build time. If APPEND is specified the COMMAND and DEPENDS
option values are appended to the custom command for the first
output specified. There must have already been a previous call
to this command with the same output. The COMMENT, WORK‐
ING_DIRECTORY, and MAIN_DEPENDENCY options are currently ignored
when APPEND is given, but may be used in the future.
If VERBATIM is given then all arguments to the commands will be
escaped properly for the build tool so that the invoked command
receives each argument unchanged. Note that one level of
escapes is still used by the CMake language processor before
add_custom_command even sees the arguments. Use of VERBATIM is
recommended as it enables correct behavior. When VERBATIM is not
given the behavior is platform specific because there is no pro‐
tection of tool-specific special characters.
If the output of the custom command is not actually created as a
file on disk it should be marked as SYMBOLIC with
SET_SOURCE_FILES_PROPERTIES.
The IMPLICIT_DEPENDS option requests scanning of implicit depen‐
dencies of an input file. The language given specifies the pro‐
gramming language whose corresponding dependency scanner should
be used. Currently only C and CXX language scanners are sup‐
ported. Dependencies discovered from the scanning are added to
those of the custom command at build time. Note that the
IMPLICIT_DEPENDS option is currently supported only for Makefile
generators and will be ignored by other generators.
If COMMAND specifies an executable target (created by ADD_EXE‐
CUTABLE) it will automatically be replaced by the location of
the executable created at build time. Additionally a tar‐
get-level dependency will be added so that the executable target
will be built before any target using this custom command. How‐
ever this does NOT add a file-level dependency that would cause
the custom command to re-run whenever the executable is recom‐
piled.
Arguments to COMMAND may use "generator expressions" with the
syntax "$<...>". Generator expressions are evaluted during
build system generation to produce information specific to each
build configuration. Valid expressions are:
$<CONFIGURATION> = configuration name
$<TARGET_FILE:tgt> = main file (.exe, .so.1.2, .a)
$<TARGET_LINKER_FILE:tgt> = file used to link (.a, .lib, .so)
$<TARGET_SONAME_FILE:tgt> = file with soname (.so.3)
where "tgt" is the name of a target. Target file expressions
produce a full path, but _DIR and _NAME versions can produce the
directory and file name components:
$<TARGET_FILE_DIR:tgt>/$<TARGET_FILE_NAME:tgt>
$<TARGET_LINKER_FILE_DIR:tgt>/$<TARGET_LINKER_FILE_NAME:tgt>
$<TARGET_SONAME_FILE_DIR:tgt>/$<TARGET_SONAME_FILE_NAME:tgt>
References to target names in generator expressions imply tar‐
get-level dependencies, but NOT file-level dependencies. List
target names with the DEPENDS option to add file dependencies.
The DEPENDS option specifies files on which the command depends.
If any dependency is an OUTPUT of another custom command in the
same directory (CMakeLists.txt file) CMake automatically brings
the other custom command into the target in which this command
is built. If DEPENDS is not specified the command will run
whenever the OUTPUT is missing; if the command does not actually
create the OUTPUT then the rule will always run. If DEPENDS
specifies any target (created by an ADD_* command) a tar‐
get-level dependency is created to make sure the target is built
before any target using this custom command. Additionally, if
the target is an executable or library a file-level dependency
is created to cause the custom command to re-run whenever the
target is recompiled.
add_custom_target
Add a target with no output so it will always be built.
add_custom_target(Name [ALL] [command1 [args1...]]
[COMMAND command2 [args2...] ...]
[DEPENDS depend depend depend ... ]
[WORKING_DIRECTORY dir]
[COMMENT comment] [VERBATIM]
[SOURCES src1 [src2...]])
Adds a target with the given name that executes the given com‐
mands. The target has no output file and is ALWAYS CONSIDERED
OUT OF DATE even if the commands try to create a file with the
name of the target. Use ADD_CUSTOM_COMMAND to generate a file
with dependencies. By default nothing depends on the custom tar‐
get. Use ADD_DEPENDENCIES to add dependencies to or from other
targets. If the ALL option is specified it indicates that this
target should be added to the default build target so that it
will be run every time (the command cannot be called ALL). The
command and arguments are optional and if not specified an empty
target will be created. If WORKING_DIRECTORY is set, then the
command will be run in that directory. If it is a relative path
it will be interpreted relative to the build tree directory cor‐
responding to the current source directory. If COMMENT is set,
the value will be displayed as a message before the commands are
executed at build time. Dependencies listed with the DEPENDS
argument may reference files and outputs of custom commands cre‐
ated with add_custom_command() in the same directory (CMake‐
Lists.txt file).
If VERBATIM is given then all arguments to the commands will be
escaped properly for the build tool so that the invoked command
receives each argument unchanged. Note that one level of
escapes is still used by the CMake language processor before
add_custom_target even sees the arguments. Use of VERBATIM is
recommended as it enables correct behavior. When VERBATIM is not
given the behavior is platform specific because there is no pro‐
tection of tool-specific special characters.
The SOURCES option specifies additional source files to be
included in the custom target. Specified source files will be
added to IDE project files for convenience in editing even if
they have not build rules.
add_definitions
Adds -D define flags to the compilation of source files.
add_definitions(-DFOO -DBAR ...)
Adds flags to the compiler command line for sources in the cur‐
rent directory and below. This command can be used to add any
flags, but it was originally intended to add preprocessor defi‐
nitions. Flags beginning in -D or /D that look like preproces‐
sor definitions are automatically added to the COMPILE_DEFINI‐
TIONS property for the current directory. Definitions with
non-trival values may be left in the set of flags instead of
being converted for reasons of backwards compatibility. See
documentation of the directory, target, and source file COM‐
PILE_DEFINITIONS properties for details on adding preprocessor
definitions to specific scopes and configurations.
add_dependencies
Add a dependency between top-level targets.
add_dependencies(target-name depend-target1
depend-target2 ...)
Make a top-level target depend on other top-level targets. A
top-level target is one created by ADD_EXECUTABLE, ADD_LIBRARY,
or ADD_CUSTOM_TARGET. Adding dependencies with this command can
be used to make sure one target is built before another target.
Dependencies added to an IMPORTED target are followed transi‐
tively in its place since the target itself does not build. See
the DEPENDS option of ADD_CUSTOM_TARGET and ADD_CUSTOM_COMMAND
for adding file-level dependencies in custom rules. See the
OBJECT_DEPENDS option in SET_SOURCE_FILES_PROPERTIES to add
file-level dependencies to object files.
add_executable
Add an executable to the project using the specified source
files.
add_executable(<name> [WIN32] [MACOSX_BUNDLE]
[EXCLUDE_FROM_ALL]
source1 source2 ... sourceN)
Adds an executable target called <name> to be built from the
source files listed in the command invocation. The <name> cor‐
responds to the logical target name and must be globally unique
within a project. The actual file name of the executable built
is constructed based on conventions of the native platform (such
as <name>.exe or just <name>).
By default the executable file will be created in the build tree
directory corresponding to the source tree directory in which
the command was invoked. See documentation of the RUNTIME_OUT‐
PUT_DIRECTORY target property to change this location. See doc‐
umentation of the OUTPUT_NAME target property to change the
<name> part of the final file name.
If WIN32 is given the property WIN32_EXECUTABLE will be set on
the target created. See documentation of that target property
for details.
If MACOSX_BUNDLE is given the corresponding property will be set
on the created target. See documentation of the MACOSX_BUNDLE
target property for details.
If EXCLUDE_FROM_ALL is given the corresponding property will be
set on the created target. See documentation of the
EXCLUDE_FROM_ALL target property for details.
The add_executable command can also create IMPORTED executable
targets using this signature:
add_executable(<name> IMPORTED [GLOBAL])
An IMPORTED executable target references an executable file
located outside the project. No rules are generated to build
it. The target name has scope in the directory in which it is
created and below, but the GLOBAL option extends visibility. It
may be referenced like any target built within the project.
IMPORTED executables are useful for convenient reference from
commands like add_custom_command. Details about the imported
executable are specified by setting properties whose names begin
in "IMPORTED_". The most important such property is
IMPORTED_LOCATION (and its per-configuration version
IMPORTED_LOCATION_<CONFIG>) which specifies the location of the
main executable file on disk. See documentation of the
IMPORTED_* properties for more information.
add_library
Add a library to the project using the specified source files.
add_library(<name> [STATIC | SHARED | MODULE]
[EXCLUDE_FROM_ALL]
source1 source2 ... sourceN)
Adds a library target called <name> to be built from the source
files listed in the command invocation. The <name> corresponds
to the logical target name and must be globally unique within a
project. The actual file name of the library built is con‐
structed based on conventions of the native platform (such as
lib<name>.a or <name>.lib).
STATIC, SHARED, or MODULE may be given to specify the type of
library to be created. STATIC libraries are archives of object
files for use when linking other targets. SHARED libraries are
linked dynamically and loaded at runtime. MODULE libraries are
plugins that are not linked into other targets but may be loaded
dynamically at runtime using dlopen-like functionality. If no
type is given explicitly the type is STATIC or SHARED based on
whether the current value of the variable BUILD_SHARED_LIBS is
true.
By default the library file will be created in the build tree
directory corresponding to the source tree directory in which
the command was invoked. See documentation of the ARCHIVE_OUT‐
PUT_DIRECTORY, LIBRARY_OUTPUT_DIRECTORY, and RUNTIME_OUT‐
PUT_DIRECTORY target properties to change this location. See
documentation of the OUTPUT_NAME target property to change the
<name> part of the final file name.
If EXCLUDE_FROM_ALL is given the corresponding property will be
set on the created target. See documentation of the
EXCLUDE_FROM_ALL target property for details.
The add_library command can also create IMPORTED library targets
using this signature:
add_library(<name> <SHARED|STATIC|MODULE|UNKNOWN> IMPORTED
[GLOBAL])
An IMPORTED library target references a library file located
outside the project. No rules are generated to build it. The
target name has scope in the directory in which it is created
and below, but the GLOBAL option extends visibility. It may be
referenced like any target built within the project. IMPORTED
libraries are useful for convenient reference from commands like
target_link_libraries. Details about the imported library are
specified by setting properties whose names begin in
"IMPORTED_". The most important such property is IMPORTED_LOCA‐
TION (and its per-configuration version IMPORTED_LOCATION_<CON‐
FIG>) which specifies the location of the main library file on
disk. See documentation of the IMPORTED_* properties for more
information.
The signature
add_library(<name> OBJECT <src>...)
creates a special "object library" target. An object library
compiles source files but does not archive or link their object
files into a library. Instead other targets created by
add_library or add_executable may reference the objects using an
expression of the form $<TARGET_OBJECTS:objlib> as a source,
where "objlib" is the object library name. For example:
add_library(... $<TARGET_OBJECTS:objlib> ...)
add_executable(... $<TARGET_OBJECTS:objlib> ...)
will include objlib's object files in a library and an exe‐
cutable along with those compiled from their own sources.
Object libraries may contain only sources (and headers) that
compile to object files. They may contain custom commands gen‐
erating such sources, but not PRE_BUILD, PRE_LINK, or POST_BUILD
commands. Object libraries cannot be imported, exported,
installed, or linked.
add_subdirectory
Add a subdirectory to the build.
add_subdirectory(source_dir [binary_dir]
[EXCLUDE_FROM_ALL])
Add a subdirectory to the build. The source_dir specifies the
directory in which the source CmakeLists.txt and code files are
located. If it is a relative path it will be evaluated with
respect to the current directory (the typical usage), but it may
also be an absolute path. The binary_dir specifies the directory
in which to place the output files. If it is a relative path it
will be evaluated with respect to the current output directory,
but it may also be an absolute path. If binary_dir is not speci‐
fied, the value of source_dir, before expanding any relative
path, will be used (the typical usage). The CMakeLists.txt file
in the specified source directory will be processed immediately
by CMake before processing in the current input file continues
beyond this command.
If the EXCLUDE_FROM_ALL argument is provided then targets in the
subdirectory will not be included in the ALL target of the par‐
ent directory by default, and will be excluded from IDE project
files. Users must explicitly build targets in the subdirectory.
This is meant for use when the subdirectory contains a separate
part of the project that is useful but not necessary, such as a
set of examples. Typically the subdirectory should contain its
own project() command invocation so that a full build system
will be generated in the subdirectory (such as a VS IDE solution
file). Note that inter-target dependencies supercede this
exclusion. If a target built by the parent project depends on a
target in the subdirectory, the dependee target will be included
in the parent project build system to satisfy the dependency.
add_test
Add a test to the project with the specified arguments.
add_test(testname Exename arg1 arg2 ... )
If the ENABLE_TESTING command has been run, this command adds a
test target to the current directory. If ENABLE_TESTING has not
been run, this command does nothing. The tests are run by the
testing subsystem by executing Exename with the specified argu‐
ments. Exename can be either an executable built by this
project or an arbitrary executable on the system (like tclsh).
The test will be run with the current working directory set to
the CMakeList.txt files corresponding directory in the binary
tree.
add_test(NAME <name> [CONFIGURATIONS [Debug|Release|...]]
[WORKING_DIRECTORY dir]
COMMAND <command> [arg1 [arg2 ...]])
If COMMAND specifies an executable target (created by add_exe‐
cutable) it will automatically be replaced by the location of
the executable created at build time. If a CONFIGURATIONS
option is given then the test will be executed only when testing
under one of the named configurations. If a WORKING_DIRECTORY
option is given then the test will be executed in the given
directory.
Arguments after COMMAND may use "generator expressions" with the
syntax "$<...>". Generator expressions are evaluted during
build system generation to produce information specific to each
build configuration. Valid expressions are:
$<CONFIGURATION> = configuration name
$<TARGET_FILE:tgt> = main file (.exe, .so.1.2, .a)
$<TARGET_LINKER_FILE:tgt> = file used to link (.a, .lib, .so)
$<TARGET_SONAME_FILE:tgt> = file with soname (.so.3)
where "tgt" is the name of a target. Target file expressions
produce a full path, but _DIR and _NAME versions can produce the
directory and file name components:
$<TARGET_FILE_DIR:tgt>/$<TARGET_FILE_NAME:tgt>
$<TARGET_LINKER_FILE_DIR:tgt>/$<TARGET_LINKER_FILE_NAME:tgt>
$<TARGET_SONAME_FILE_DIR:tgt>/$<TARGET_SONAME_FILE_NAME:tgt>
Example usage:
add_test(NAME mytest
COMMAND testDriver --config $<CONFIGURATION>
--exe $<TARGET_FILE:myexe>)
This creates a test "mytest" whose command runs a testDriver
tool passing the configuration name and the full path to the
executable file produced by target "myexe".
aux_source_directory
Find all source files in a directory.
aux_source_directory(<dir> <variable>)
Collects the names of all the source files in the specified
directory and stores the list in the <variable> provided. This
command is intended to be used by projects that use explicit
template instantiation. Template instantiation files can be
stored in a "Templates" subdirectory and collected automatically
using this command to avoid manually listing all instantiations.
It is tempting to use this command to avoid writing the list of
source files for a library or executable target. While this
seems to work, there is no way for CMake to generate a build
system that knows when a new source file has been added. Nor‐
mally the generated build system knows when it needs to rerun
CMake because the CMakeLists.txt file is modified to add a new
source. When the source is just added to the directory without
modifying this file, one would have to manually rerun CMake to
generate a build system incorporating the new file.
break Break from an enclosing foreach or while loop.
break()
Breaks from an enclosing foreach loop or while loop
build_command
Get the command line to build this project.
build_command(<variable>
[CONFIGURATION <config>]
[PROJECT_NAME <projname>]
[TARGET <target>])
Sets the given <variable> to a string containing the command
line for building one configuration of a target in a project
using the build tool appropriate for the current CMAKE_GENERA‐
TOR.
If CONFIGURATION is omitted, CMake chooses a reasonable default
value for multi-configuration generators. CONFIGURATION is
ignored for single-configuration generators.
If PROJECT_NAME is omitted, the resulting command line will
build the top level PROJECT in the current build tree.
If TARGET is omitted, the resulting command line will build
everything, effectively using build target 'all' or 'ALL_BUILD'.
build_command(<cachevariable> <makecommand>)
This second signature is deprecated, but still available for
backwards compatibility. Use the first signature instead.
Sets the given <cachevariable> to a string containing the com‐
mand to build this project from the root of the build tree using
the build tool given by <makecommand>. <makecommand> should be
the full path to msdev, devenv, nmake, make or one of the end
user build tools.
cmake_minimum_required
Set the minimum required version of cmake for a project.
cmake_minimum_required(VERSION major[.minor[.patch[.tweak]]]
[FATAL_ERROR])
If the current version of CMake is lower than that required it
will stop processing the project and report an error. When a
version higher than 2.4 is specified the command implicitly
invokes
cmake_policy(VERSION major[.minor[.patch[.tweak]]])
which sets the cmake policy version level to the version speci‐
fied. When version 2.4 or lower is given the command implicitly
invokes
cmake_policy(VERSION 2.4)
which enables compatibility features for CMake 2.4 and lower.
The FATAL_ERROR option is accepted but ignored by CMake 2.6 and
higher. It should be specified so CMake versions 2.4 and lower
fail with an error instead of just a warning.
cmake_policy
Manage CMake Policy settings.
As CMake evolves it is sometimes necessary to change existing
behavior in order to fix bugs or improve implementations of
existing features. The CMake Policy mechanism is designed to
help keep existing projects building as new versions of CMake
introduce changes in behavior. Each new policy (behavioral
change) is given an identifier of the form "CMP<NNNN>" where
"<NNNN>" is an integer index. Documentation associated with
each policy describes the OLD and NEW behavior and the reason
the policy was introduced. Projects may set each policy to
select the desired behavior. When CMake needs to know which
behavior to use it checks for a setting specified by the
project. If no setting is available the OLD behavior is assumed
and a warning is produced requesting that the policy be set.
The cmake_policy command is used to set policies to OLD or NEW
behavior. While setting policies individually is supported, we
encourage projects to set policies based on CMake versions.
cmake_policy(VERSION major.minor[.patch[.tweak]])
Specify that the current CMake list file is written for the
given version of CMake. All policies introduced in the speci‐
fied version or earlier will be set to use NEW behavior. All
policies introduced after the specified version will be unset
(unless variable CMAKE_POLICY_DEFAULT_CMP<NNNN> sets a default).
This effectively requests behavior preferred as of a given CMake
version and tells newer CMake versions to warn about their new
policies. The policy version specified must be at least 2.4 or
the command will report an error. In order to get compatibility
features supporting versions earlier than 2.4 see documentation
of policy CMP0001.
cmake_policy(SET CMP<NNNN> NEW)
cmake_policy(SET CMP<NNNN> OLD)
Tell CMake to use the OLD or NEW behavior for a given policy.
Projects depending on the old behavior of a given policy may
silence a policy warning by setting the policy state to OLD.
Alternatively one may fix the project to work with the new
behavior and set the policy state to NEW.
cmake_policy(GET CMP<NNNN> <variable>)
Check whether a given policy is set to OLD or NEW behavior. The
output variable value will be "OLD" or "NEW" if the policy is
set, and empty otherwise.
CMake keeps policy settings on a stack, so changes made by the
cmake_policy command affect only the top of the stack. A new
entry on the policy stack is managed automatically for each sub‐
directory to protect its parents and siblings. CMake also man‐
ages a new entry for scripts loaded by include() and find_pack‐
age() commands except when invoked with the NO_POLICY_SCOPE
option (see also policy CMP0011). The cmake_policy command pro‐
vides an interface to manage custom entries on the policy stack:
cmake_policy(PUSH)cmake_policy(POP)
Each PUSH must have a matching POP to erase any changes. This
is useful to make temporary changes to policy settings.
Functions and macros record policy settings when they are cre‐
ated and use the pre-record policies when they are invoked. If
the function or macro implementation sets policies, the changes
automatically propagate up through callers until they reach the
closest nested policy stack entry.
configure_file
Copy a file to another location and modify its contents.
configure_file(<input> <output>
[COPYONLY] [ESCAPE_QUOTES] [@ONLY]
[NEWLINE_STYLE [UNIX|DOS|WIN32|LF|CRLF] ])
Copies a file <input> to file <output> and substitutes variable
values referenced in the file content. If <input> is a relative
path it is evaluated with respect to the current source direc‐
tory. The <input> must be a file, not a directory. If <output>
is a relative path it is evaluated with respect to the current
binary directory. If <output> names an existing directory the
input file is placed in that directory with its original name.
This command replaces any variables in the input file referenced
as ${VAR} or @VAR@ with their values as determined by CMake. If
a variable is not defined, it will be replaced with nothing. If
COPYONLY is specified, then no variable expansion will take
place. If ESCAPE_QUOTES is specified then any substituted
quotes will be C-style escaped. The file will be configured
with the current values of CMake variables. If @ONLY is speci‐
fied, only variables of the form @VAR@ will be replaces and
${VAR} will be ignored. This is useful for configuring scripts
that use ${VAR}. Any occurrences of #cmakedefine VAR will be
replaced with either #define VAR or /* #undef VAR */ depending
on the setting of VAR in CMake. Any occurrences of #cmakede‐
fine01 VAR will be replaced with either #define VAR 1 or #define
VAR 0 depending on whether VAR evaluates to TRUE or FALSE in
CMake.
With NEWLINE_STYLE the line ending could be adjusted:
'UNIX' or 'LF' for \n, 'DOS', 'WIN32' or 'CRLF' for \r\n.
COPYONLY must not be used with NEWLINE_STYLE.
create_test_sourcelist
Create a test driver and source list for building test programs.
create_test_sourcelist(sourceListName driverName
test1 test2 test3
EXTRA_INCLUDE include.h
FUNCTION function)
A test driver is a program that links together many small tests
into a single executable. This is useful when building static
executables with large libraries to shrink the total required
size. The list of source files needed to build the test driver
will be in sourceListName. DriverName is the name of the test
driver program. The rest of the arguments consist of a list of
test source files, can be semicolon separated. Each test source
file should have a function in it that is the same name as the
file with no extension (foo.cxx should have int foo(int,
char*[]);) DriverName will be able to call each of the tests by
name on the command line. If EXTRA_INCLUDE is specified, then
the next argument is included into the generated file. If FUNC‐
TION is specified, then the next argument is taken as a function
name that is passed a pointer to ac and av. This can be used to
add extra command line processing to each test. The cmake vari‐
able CMAKE_TESTDRIVER_BEFORE_TESTMAIN can be set to have code
that will be placed directly before calling the test main func‐
tion. CMAKE_TESTDRIVER_AFTER_TESTMAIN can be set to have code
that will be placed directly after the call to the test main
function.
define_property
Define and document custom properties.
define_property(<GLOBAL | DIRECTORY | TARGET | SOURCE |
TEST | VARIABLE | CACHED_VARIABLE>
PROPERTY <name> [INHERITED]
BRIEF_DOCS <brief-doc> [docs...]
FULL_DOCS <full-doc> [docs...])
Define one property in a scope for use with the set_property and
get_property commands. This is primarily useful to associate
documentation with property names that may be retrieved with the
get_property command. The first argument determines the kind of
scope in which the property should be used. It must be one of
the following:
GLOBAL = associated with the global namespace
DIRECTORY = associated with one directory
TARGET = associated with one target
SOURCE = associated with one source file
TEST = associated with a test named with add_test
VARIABLE = documents a CMake language variable
CACHED_VARIABLE = documents a CMake cache variable
Note that unlike set_property and get_property no actual scope
needs to be given; only the kind of scope is important.
The required PROPERTY option is immediately followed by the name
of the property being defined.
If the INHERITED option then the get_property command will chain
up to the next higher scope when the requested property is not
set in the scope given to the command. DIRECTORY scope chains
to GLOBAL. TARGET, SOURCE, and TEST chain to DIRECTORY.
The BRIEF_DOCS and FULL_DOCS options are followed by strings to
be associated with the property as its brief and full documenta‐
tion. Corresponding options to the get_property command will
retrieve the documentation.
else Starts the else portion of an if block.
else(expression)
See the if command.
elseif Starts the elseif portion of an if block.
elseif(expression)
See the if command.
enable_language
Enable a language (CXX/C/Fortran/etc)
enable_language(languageName [OPTIONAL] )
This command enables support for the named language in CMake.
This is the same as the project command but does not create any
of the extra variables that are created by the project command.
Example languages are CXX, C, Fortran. If OPTIONAL is used, use
the CMAKE_<languageName>_COMPILER_WORKS variable to check
whether the language has been enabled successfully.
enable_testing
Enable testing for current directory and below.
enable_testing()
Enables testing for this directory and below. See also the
add_test command. Note that ctest expects to find a test file
in the build directory root. Therefore, this command should be
in the source directory root.
endforeach
Ends a list of commands in a FOREACH block.
endforeach(expression)
See the FOREACH command.
endfunction
Ends a list of commands in a function block.
endfunction(expression)
See the function command.
endif Ends a list of commands in an if block.
endif(expression)
See the if command.
endmacro
Ends a list of commands in a macro block.
endmacro(expression)
See the macro command.
endwhile
Ends a list of commands in a while block.
endwhile(expression)
See the while command.
execute_process
Execute one or more child processes.
execute_process(COMMAND <cmd1> [args1...]]
[COMMAND <cmd2> [args2...] [...]]
[WORKING_DIRECTORY <directory>]
[TIMEOUT <seconds>]
[RESULT_VARIABLE <variable>]
[OUTPUT_VARIABLE <variable>]
[ERROR_VARIABLE <variable>]
[INPUT_FILE <file>]
[OUTPUT_FILE <file>]
[ERROR_FILE <file>]
[OUTPUT_QUIET]
[ERROR_QUIET]
[OUTPUT_STRIP_TRAILING_WHITESPACE]
[ERROR_STRIP_TRAILING_WHITESPACE])
Runs the given sequence of one or more commands with the stan‐
dard output of each process piped to the standard input of the
next. A single standard error pipe is used for all processes.
If WORKING_DIRECTORY is given the named directory will be set as
the current working directory of the child processes. If TIME‐
OUT is given the child processes will be terminated if they do
not finish in the specified number of seconds (fractions are
allowed). If RESULT_VARIABLE is given the variable will be set
to contain the result of running the processes. This will be an
integer return code from the last child or a string describing
an error condition. If OUTPUT_VARIABLE or ERROR_VARIABLE are
given the variable named will be set with the contents of the
standard output and standard error pipes respectively. If the
same variable is named for both pipes their output will be
merged in the order produced. If INPUT_FILE, OUTPUT_FILE, or
ERROR_FILE is given the file named will be attached to the stan‐
dard input of the first process, standard output of the last
process, or standard error of all processes respectively. If
OUTPUT_QUIET or ERROR_QUIET is given then the standard output or
standard error results will be quietly ignored. If more than
one OUTPUT_* or ERROR_* option is given for the same pipe the
precedence is not specified. If no OUTPUT_* or ERROR_* options
are given the output will be shared with the corresponding pipes
of the CMake process itself.
The execute_process command is a newer more powerful version of
exec_program, but the old command has been kept for compatibil‐
ity.
export Export targets from the build tree for use by outside projects.
export(TARGETS [target1 [target2 [...]]] [NAMESPACE <namespace>]
[APPEND] FILE <filename>)
Create a file <filename> that may be included by outside
projects to import targets from the current project's build
tree. This is useful during cross-compiling to build utility
executables that can run on the host platform in one project and
then import them into another project being compiled for the
target platform. If the NAMESPACE option is given the <names‐
pace> string will be prepended to all target names written to
the file. If the APPEND option is given the generated code will
be appended to the file instead of overwriting it. If a library
target is included in the export but a target to which it links
is not included the behavior is unspecified.
The file created by this command is specific to the build tree
and should never be installed. See the install(EXPORT) command
to export targets from an installation tree.
Do not set properties that affect the location of a target after
passing it to this command. These include properties whose
names match "(RUNTIME|LIBRARY|ARCHIVE)_OUTPUT_(NAME|DIREC‐
TORY)(_<CONFIG>)?" or "(IMPLIB_)?(PREFIX|SUFFIX)". Failure to
follow this rule is not diagnosed and leaves the location of the
target undefined.
export(PACKAGE <name>)
Store the current build directory in the CMake user package reg‐
istry for package <name>. The find_package command may consider
the directory while searching for package <name>. This helps
dependent projects find and use a package from the current
project's build tree without help from the user. Note that the
entry in the package registry that this command creates works
only in conjunction with a package configuration file
(<name>Config.cmake) that works with the build tree.
file File manipulation command.
file(WRITE filename "message to write"... )
file(APPEND filename "message to write"... )
file(READ filename variable [LIMIT numBytes] [OFFSET offset] [HEX])
file(<MD5|SHA1|SHA224|SHA256|SHA384|SHA512> filename variable)
file(STRINGS filename variable [LIMIT_COUNT num]
[LIMIT_INPUT numBytes] [LIMIT_OUTPUT numBytes]
[LENGTH_MINIMUM numBytes] [LENGTH_MAXIMUM numBytes]
[NEWLINE_CONSUME] [REGEX regex]
[NO_HEX_CONVERSION])
file(GLOB variable [RELATIVE path] [globbing expressions]...)
file(GLOB_RECURSE variable [RELATIVE path]
[FOLLOW_SYMLINKS] [globbing expressions]...)
file(RENAME <oldname> <newname>)
file(REMOVE [file1 ...])
file(REMOVE_RECURSE [file1 ...])
file(MAKE_DIRECTORY [directory1 directory2 ...])
file(RELATIVE_PATH variable directory file)
file(TO_CMAKE_PATH path result)
file(TO_NATIVE_PATH path result)
file(DOWNLOAD url file [INACTIVITY_TIMEOUT timeout]
[TIMEOUT timeout] [STATUS status] [LOG log] [SHOW_PROGRESS]
[EXPECTED_MD5 sum])
file(UPLOAD filename url [INACTIVITY_TIMEOUT timeout]
[TIMEOUT timeout] [STATUS status] [LOG log] [SHOW_PROGRESS])
WRITE will write a message into a file called 'filename'. It
overwrites the file if it already exists, and creates the file
if it does not exist.
APPEND will write a message into a file same as WRITE, except it
will append it to the end of the file
READ will read the content of a file and store it into the vari‐
able. It will start at the given offset and read up to numBytes.
If the argument HEX is given, the binary data will be converted
to hexadecimal representation and this will be stored in the
variable.
MD5, SHA1, SHA224, SHA256, SHA384, and SHA512 will compute a
cryptographic hash of the content of a file.
STRINGS will parse a list of ASCII strings from a file and store
it in a variable. Binary data in the file are ignored. Carriage
return (CR) characters are ignored. It works also for Intel Hex
and Motorola S-record files, which are automatically converted
to binary format when reading them. Disable this using
NO_HEX_CONVERSION.
LIMIT_COUNT sets the maximum number of strings to return.
LIMIT_INPUT sets the maximum number of bytes to read from the
input file. LIMIT_OUTPUT sets the maximum number of bytes to
store in the output variable. LENGTH_MINIMUM sets the minimum
length of a string to return. Shorter strings are ignored.
LENGTH_MAXIMUM sets the maximum length of a string to return.
Longer strings are split into strings no longer than the maximum
length. NEWLINE_CONSUME allows newlines to be included in
strings instead of terminating them.
REGEX specifies a regular expression that a string must match to
be returned. Typical usage
file(STRINGS myfile.txt myfile)
stores a list in the variable "myfile" in which each item is a
line from the input file.
GLOB will generate a list of all files that match the globbing
expressions and store it into the variable. Globbing expressions
are similar to regular expressions, but much simpler. If RELA‐
TIVE flag is specified for an expression, the results will be
returned as a relative path to the given path. (We do not rec‐
ommend using GLOB to collect a list of source files from your
source tree. If no CMakeLists.txt file changes when a source is
added or removed then the generated build system cannot know
when to ask CMake to regenerate.)
Examples of globbing expressions include:
*.cxx - match all files with extension cxx
*.vt? - match all files with extension vta,...,vtz
f[3-5].txt - match files f3.txt, f4.txt, f5.txt
GLOB_RECURSE will generate a list similar to the regular GLOB,
except it will traverse all the subdirectories of the matched
directory and match the files. Subdirectories that are symlinks
are only traversed if FOLLOW_SYMLINKS is given or cmake policy
CMP0009 is not set to NEW. See cmake --help-policy CMP0009 for
more information.
Examples of recursive globbing include:
/dir/*.py - match all python files in /dir and subdirectories
MAKE_DIRECTORY will create the given directories, also if their
parent directories don't exist yet
RENAME moves a file or directory within a filesystem, replacing
the destination atomically.
REMOVE will remove the given files, also in subdirectories
REMOVE_RECURSE will remove the given files and directories, also
non-empty directories
RELATIVE_PATH will determine relative path from directory to the
given file.
TO_CMAKE_PATH will convert path into a cmake style path with
unix /. The input can be a single path or a system path like
"$ENV{PATH}". Note the double quotes around the ENV call
TO_CMAKE_PATH only takes one argument. This command will also
convert the native list delimiters for a list of paths like the
PATH environment variable.
TO_NATIVE_PATH works just like TO_CMAKE_PATH, but will convert
from a cmake style path into the native path style \ for win‐
dows and / for UNIX.
DOWNLOAD will download the given URL to the given file. If LOG
var is specified a log of the download will be put in var. If
STATUS var is specified the status of the operation will be put
in var. The status is returned in a list of length 2. The first
element is the numeric return value for the operation, and the
second element is a string value for the error. A 0 numeric
error means no error in the operation. If TIMEOUT time is speci‐
fied, the operation will timeout after time seconds, time should
be specified as an integer. The INACTIVITY_TIMEOUT specifies an
integer number of seconds of inactivity after which the opera‐
tion should terminate. If EXPECTED_MD5 sum is specified, the
operation will verify that the downloaded file's actual md5 sum
matches the expected value. If it does not match, the operation
fails with an error. If SHOW_PROGRESS is specified, progress
information will be printed as status messages until the opera‐
tion is complete.
UPLOAD will upload the given file to the given URL. If LOG var
is specified a log of the upload will be put in var. If STATUS
var is specified the status of the operation will be put in var.
The status is returned in a list of length 2. The first element
is the numeric return value for the operation, and the second
element is a string value for the error. A 0 numeric error means
no error in the operation. If TIMEOUT time is specified, the
operation will timeout after time seconds, time should be speci‐
fied as an integer. The INACTIVITY_TIMEOUT specifies an integer
number of seconds of inactivity after which the operation should
terminate. If SHOW_PROGRESS is specified, progress information
will be printed as status messages until the operation is com‐
plete.
The file() command also provides COPY and INSTALL signatures:
file(<COPY|INSTALL> files... DESTINATION <dir>
[FILE_PERMISSIONS permissions...]
[DIRECTORY_PERMISSIONS permissions...]
[NO_SOURCE_PERMISSIONS] [USE_SOURCE_PERMISSIONS]
[FILES_MATCHING]
[[PATTERN <pattern> | REGEX <regex>]
[EXCLUDE] [PERMISSIONS permissions...]] [...])
The COPY signature copies files, directories, and symlinks to a
destination folder. Relative input paths are evaluated with
respect to the current source directory, and a relative destina‐
tion is evaluated with respect to the current build directory.
Copying preserves input file timestamps, and optimizes out a
file if it exists at the destination with the same timestamp.
Copying preserves input permissions unless explicit permissions
or NO_SOURCE_PERMISSIONS are given (default is USE_SOURCE_PER‐
MISSIONS). See the install(DIRECTORY) command for documentation
of permissions, PATTERN, REGEX, and EXCLUDE options.
The INSTALL signature differs slightly from COPY: it prints sta‐
tus messages, and NO_SOURCE_PERMISSIONS is default. Installa‐
tion scripts generated by the install() command use this signa‐
ture (with some undocumented options for internal use).
find_file
Find the full path to a file.
find_file(<VAR> name1 [path1 path2 ...])
This is the short-hand signature for the command that is suffi‐
cient in many cases. It is the same as find_file(<VAR> name1
[PATHS path1 path2 ...])
find_file(
<VAR>
name | NAMES name1 [name2 ...]
[HINTS path1 [path2 ... ENV var]]
[PATHS path1 [path2 ... ENV var]]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[DOC "cache documentation string"]
[NO_DEFAULT_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_CMAKE_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_SYSTEM_PATH]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH]
)
This command is used to find a full path to named file. A cache
entry named by <VAR> is created to store the result of this com‐
mand. If the full path to a file is found the result is stored
in the variable and the search will not be repeated unless the
variable is cleared. If nothing is found, the result will be
<VAR>-NOTFOUND, and the search will be attempted again the next
time find_file is invoked with the same variable. The name of
the full path to a file that is searched for is specified by the
names listed after the NAMES argument. Additional search loca‐
tions can be specified after the PATHS argument. If ENV var is
found in the HINTS or PATHS section the environment variable var
will be read and converted from a system environment variable to
a cmake style list of paths. For example ENV PATH would be a
way to list the system path variable. The argument after DOC
will be used for the documentation string in the cache.
PATH_SUFFIXES specifies additional subdirectories to check below
each search path.
If NO_DEFAULT_PATH is specified, then no additional paths are
added to the search. If NO_DEFAULT_PATH is not specified, the
search process is as follows:
1. Search paths specified in cmake-specific cache variables.
These are intended to be used on the command line with a
-DVAR=value. This can be skipped if NO_CMAKE_PATH is passed.
<prefix>/include for each <prefix> in CMAKE_PREFIX_PATH
CMAKE_INCLUDE_PATH
CMAKE_FRAMEWORK_PATH
2. Search paths specified in cmake-specific environment vari‐
ables. These are intended to be set in the user's shell config‐
uration. This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed.
<prefix>/include for each <prefix> in CMAKE_PREFIX_PATH
CMAKE_INCLUDE_PATH
CMAKE_FRAMEWORK_PATH
3. Search the paths specified by the HINTS option. These should
be paths computed by system introspection, such as a hint pro‐
vided by the location of another item already found. Hard-coded
guesses should be specified with the PATHS option.
4. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is an argument.
PATH
INCLUDE
5. Search cmake variables defined in the Platform files for the
current system. This can be skipped if NO_CMAKE_SYSTEM_PATH is
passed.
<prefix>/include for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH
CMAKE_SYSTEM_INCLUDE_PATH
CMAKE_SYSTEM_FRAMEWORK_PATH
6. Search the paths specified by the PATHS option or in the
short-hand version of the command. These are typically
hard-coded guesses.
On Darwin or systems supporting OS X Frameworks, the cmake vari‐
able CMAKE_FIND_FRAMEWORK can be set to empty or one of the
following:
"FIRST" - Try to find frameworks before standard
libraries or headers. This is the default on Darwin.
"LAST" - Try to find frameworks after standard
libraries or headers.
"ONLY" - Only try to find frameworks.
"NEVER" - Never try to find frameworks.
On Darwin or systems supporting OS X Application Bundles, the
cmake variable CMAKE_FIND_APPBUNDLE can be set to empty or one
of the following:
"FIRST" - Try to find application bundles before standard
programs. This is the default on Darwin.
"LAST" - Try to find application bundles after standard
programs.
"ONLY" - Only try to find application bundles.
"NEVER" - Never try to find application bundles.
The CMake variable CMAKE_FIND_ROOT_PATH specifies one or more
directories to be prepended to all other search directories.
This effectively "re-roots" the entire search under given loca‐
tions. By default it is empty. It is especially useful when
cross-compiling to point to the root directory of the target
environment and CMake will search there too. By default at first
the directories listed in CMAKE_FIND_ROOT_PATH and then the
non-rooted directories will be searched. The default behavior
can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_INCLUDE.
This behavior can be manually overridden on a per-call basis. By
using CMAKE_FIND_ROOT_PATH_BOTH the search order will be as
described above. If NO_CMAKE_FIND_ROOT_PATH is used then
CMAKE_FIND_ROOT_PATH will not be used. If
ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted direc‐
tories will be searched.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the
order by simply calling the command multiple times and using the
NO_* options:
find_file(<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
find_file(<VAR> NAMES name)
Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.
find_library
Find a library.
find_library(<VAR> name1 [path1 path2 ...])
This is the short-hand signature for the command that is suffi‐
cient in many cases. It is the same as find_library(<VAR> name1
[PATHS path1 path2 ...])
find_library(
<VAR>
name | NAMES name1 [name2 ...]
[HINTS path1 [path2 ... ENV var]]
[PATHS path1 [path2 ... ENV var]]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[DOC "cache documentation string"]
[NO_DEFAULT_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_CMAKE_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_SYSTEM_PATH]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH]
)
This command is used to find a library. A cache entry named by
<VAR> is created to store the result of this command. If the
library is found the result is stored in the variable and the
search will not be repeated unless the variable is cleared. If
nothing is found, the result will be <VAR>-NOTFOUND, and the
search will be attempted again the next time find_library is
invoked with the same variable. The name of the library that is
searched for is specified by the names listed after the NAMES
argument. Additional search locations can be specified after
the PATHS argument. If ENV var is found in the HINTS or PATHS
section the environment variable var will be read and converted
from a system environment variable to a cmake style list of
paths. For example ENV PATH would be a way to list the system
path variable. The argument after DOC will be used for the docu‐
mentation string in the cache. PATH_SUFFIXES specifies addi‐
tional subdirectories to check below each search path.
If NO_DEFAULT_PATH is specified, then no additional paths are
added to the search. If NO_DEFAULT_PATH is not specified, the
search process is as follows:
1. Search paths specified in cmake-specific cache variables.
These are intended to be used on the command line with a
-DVAR=value. This can be skipped if NO_CMAKE_PATH is passed.
<prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and
<prefix>/lib for each <prefix> in CMAKE_PREFIX_PATH
CMAKE_LIBRARY_PATH
CMAKE_FRAMEWORK_PATH
2. Search paths specified in cmake-specific environment vari‐
ables. These are intended to be set in the user's shell config‐
uration. This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed.
<prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and
<prefix>/lib for each <prefix> in CMAKE_PREFIX_PATH
CMAKE_LIBRARY_PATH
CMAKE_FRAMEWORK_PATH
3. Search the paths specified by the HINTS option. These should
be paths computed by system introspection, such as a hint pro‐
vided by the location of another item already found. Hard-coded
guesses should be specified with the PATHS option.
4. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is an argument.
PATH
LIB
5. Search cmake variables defined in the Platform files for the
current system. This can be skipped if NO_CMAKE_SYSTEM_PATH is
passed.
<prefix>/lib/<arch> if CMAKE_LIBRARY_ARCHITECTURE is set, and
<prefix>/lib for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH
CMAKE_SYSTEM_LIBRARY_PATH
CMAKE_SYSTEM_FRAMEWORK_PATH
6. Search the paths specified by the PATHS option or in the
short-hand version of the command. These are typically
hard-coded guesses.
On Darwin or systems supporting OS X Frameworks, the cmake vari‐
able CMAKE_FIND_FRAMEWORK can be set to empty or one of the
following:
"FIRST" - Try to find frameworks before standard
libraries or headers. This is the default on Darwin.
"LAST" - Try to find frameworks after standard
libraries or headers.
"ONLY" - Only try to find frameworks.
"NEVER" - Never try to find frameworks.
On Darwin or systems supporting OS X Application Bundles, the
cmake variable CMAKE_FIND_APPBUNDLE can be set to empty or one
of the following:
"FIRST" - Try to find application bundles before standard
programs. This is the default on Darwin.
"LAST" - Try to find application bundles after standard
programs.
"ONLY" - Only try to find application bundles.
"NEVER" - Never try to find application bundles.
The CMake variable CMAKE_FIND_ROOT_PATH specifies one or more
directories to be prepended to all other search directories.
This effectively "re-roots" the entire search under given loca‐
tions. By default it is empty. It is especially useful when
cross-compiling to point to the root directory of the target
environment and CMake will search there too. By default at first
the directories listed in CMAKE_FIND_ROOT_PATH and then the
non-rooted directories will be searched. The default behavior
can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_LIBRARY.
This behavior can be manually overridden on a per-call basis. By
using CMAKE_FIND_ROOT_PATH_BOTH the search order will be as
described above. If NO_CMAKE_FIND_ROOT_PATH is used then
CMAKE_FIND_ROOT_PATH will not be used. If
ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted direc‐
tories will be searched.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the
order by simply calling the command multiple times and using the
NO_* options:
find_library(<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
find_library(<VAR> NAMES name)
Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.
If the library found is a framework, then VAR will be set to the
full path to the framework <fullPath>/A.framework. When a full
path to a framework is used as a library, CMake will use a
-framework A, and a -F<fullPath> to link the framework to the
target.
If the global property FIND_LIBRARY_USE_LIB64_PATHS is set all
search paths will be tested as normal, with "64/" appended, and
with all matches of "lib/" replaced with "lib64/". This property
is automatically set for the platforms that are known to need it
if at least one of the languages supported by the PROJECT com‐
mand is enabled.
find_package
Load settings for an external project.
find_package(<package> [version] [EXACT] [QUIET] [MODULE]
[REQUIRED] [[COMPONENTS] [components...]]
[OPTIONAL_COMPONENTS components...]
[NO_POLICY_SCOPE])
Finds and loads settings from an external project. <pack‐
age>_FOUND will be set to indicate whether the package was
found. When the package is found package-specific information
is provided through variables documented by the package itself.
The QUIET option disables messages if the package cannot be
found. The MODULE option disables the second signature docu‐
mented below. The REQUIRED option stops processing with an
error message if the package cannot be found.
A package-specific list of required components may be listed
after the COMPONENTS option (or after the REQUIRED option if
present). Additional optional components may be listed after
OPTIONAL_COMPONENTS. Available components and their influence
on whether a package is considered to be found are defined by
the target package.
The [version] argument requests a version with which the package
found should be compatible (format is
major[.minor[.patch[.tweak]]]). The EXACT option requests that
the version be matched exactly. If no [version] and/or compo‐
nent list is given to a recursive invocation inside a find-mod‐
ule, the corresponding arguments are forwarded automatically
from the outer call (including the EXACT flag for [version]).
Version support is currently provided only on a package-by-pack‐
age basis (details below).
User code should generally look for packages using the above
simple signature. The remainder of this command documentation
specifies the full command signature and details of the search
process. Project maintainers wishing to provide a package to be
found by this command are encouraged to read on.
The command has two modes by which it searches for packages:
"Module" mode and "Config" mode. Module mode is available when
the command is invoked with the above reduced signature. CMake
searches for a file called "Find<package>.cmake" in the
CMAKE_MODULE_PATH followed by the CMake installation. If the
file is found, it is read and processed by CMake. It is respon‐
sible for finding the package, checking the version, and produc‐
ing any needed messages. Many find-modules provide limited or
no support for versioning; check the module documentation. If
no module is found and the MODULE option is not given the com‐
mand proceeds to Config mode.
The complete Config mode command signature is:
find_package(<package> [version] [EXACT] [QUIET]
[REQUIRED] [[COMPONENTS] [components...]]
[CONFIG|NO_MODULE]
[NO_POLICY_SCOPE]
[NAMES name1 [name2 ...]]
[CONFIGS config1 [config2 ...]]
[HINTS path1 [path2 ... ]]
[PATHS path1 [path2 ... ]]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[NO_DEFAULT_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_CMAKE_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_PACKAGE_REGISTRY]
[NO_CMAKE_BUILDS_PATH]
[NO_CMAKE_SYSTEM_PATH]
[NO_CMAKE_SYSTEM_PACKAGE_REGISTRY]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH])
The CONFIG option may be used to skip Module mode explicitly and
switch to Config mode. It is synonymous to using NO_MODULE.
Config mode is also implied by use of options not specified in
the reduced signature.
Config mode attempts to locate a configuration file provided by
the package to be found. A cache entry called <package>_DIR is
created to hold the directory containing the file. By default
the command searches for a package with the name <package>. If
the NAMES option is given the names following it are used
instead of <package>. The command searches for a file called
"<name>Config.cmake" or "<lower-case-name>-config.cmake" for
each name specified. A replacement set of possible configura‐
tion file names may be given using the CONFIGS option. The
search procedure is specified below. Once found, the configura‐
tion file is read and processed by CMake. Since the file is
provided by the package it already knows the location of package
contents. The full path to the configuration file is stored in
the cmake variable <package>_CONFIG.
All configuration files which have been considered by CMake
while searching for an installation of the package with an
appropriate version are stored in the cmake variable <pack‐
age>_CONSIDERED_CONFIGS, the associated versions in <pack‐
age>_CONSIDERED_VERSIONS.
If the package configuration file cannot be found CMake will
generate an error describing the problem unless the QUIET argu‐
ment is specified. If REQUIRED is specified and the package is
not found a fatal error is generated and the configure step
stops executing. If <package>_DIR has been set to a directory
not containing a configuration file CMake will ignore it and
search from scratch.
When the [version] argument is given Config mode will only find
a version of the package that claims compatibility with the
requested version (format is major[.minor[.patch[.tweak]]]). If
the EXACT option is given only a version of the package claiming
an exact match of the requested version may be found. CMake
does not establish any convention for the meaning of version
numbers. Package version numbers are checked by "version" files
provided by the packages themselves. For a candidate package
configuration file "<config-file>.cmake" the corresponding ver‐
sion file is located next to it and named either "<con‐
fig-file>-version.cmake" or "<config-file>Version.cmake". If no
such version file is available then the configuration file is
assumed to not be compatible with any requested version. A
basic version file containing generic version matching code can
be created using the macro write_basic_package_version_file(),
see its documentation for more details. When a version file is
found it is loaded to check the requested version number. The
version file is loaded in a nested scope in which the following
variables have been defined:
PACKAGE_FIND_NAME = the <package> name
PACKAGE_FIND_VERSION = full requested version string
PACKAGE_FIND_VERSION_MAJOR = major version if requested, else 0
PACKAGE_FIND_VERSION_MINOR = minor version if requested, else 0
PACKAGE_FIND_VERSION_PATCH = patch version if requested, else 0
PACKAGE_FIND_VERSION_TWEAK = tweak version if requested, else 0
PACKAGE_FIND_VERSION_COUNT = number of version components, 0 to 4
The version file checks whether it satisfies the requested ver‐
sion and sets these variables:
PACKAGE_VERSION = full provided version string
PACKAGE_VERSION_EXACT = true if version is exact match
PACKAGE_VERSION_COMPATIBLE = true if version is compatible
PACKAGE_VERSION_UNSUITABLE = true if unsuitable as any version
These variables are checked by the find_package command to
determine whether the configuration file provides an acceptable
version. They are not available after the find_package call
returns. If the version is acceptable the following variables
are set:
<package>_VERSION = full provided version string
<package>_VERSION_MAJOR = major version if provided, else 0
<package>_VERSION_MINOR = minor version if provided, else 0
<package>_VERSION_PATCH = patch version if provided, else 0
<package>_VERSION_TWEAK = tweak version if provided, else 0
<package>_VERSION_COUNT = number of version components, 0 to 4
and the corresponding package configuration file is loaded.
When multiple package configuration files are available whose
version files claim compatibility with the version requested it
is unspecified which one is chosen. No attempt is made to
choose a highest or closest version number.
Config mode provides an elaborate interface and search proce‐
dure. Much of the interface is provided for completeness and
for use internally by find-modules loaded by Module mode. Most
user code should simply call
find_package(<package> [major[.minor]] [EXACT] [REQUIRED|QUIET])
in order to find a package. Package maintainers providing CMake
package configuration files are encouraged to name and install
them such that the procedure outlined below will find them with‐
out requiring use of additional options.
CMake constructs a set of possible installation prefixes for the
package. Under each prefix several directories are searched for
a configuration file. The tables below show the directories
searched. Each entry is meant for installation trees following
Windows (W), UNIX (U), or Apple (A) conventions.
<prefix>/ (W)
<prefix>/(cmake|CMake)/ (W)
<prefix>/<name>*/ (W)
<prefix>/<name>*/(cmake|CMake)/ (W)
<prefix>/(lib/<arch>|lib|share)/cmake/<name>*/ (U)
<prefix>/(lib/<arch>|lib|share)/<name>*/ (U)
<prefix>/(lib/<arch>|lib|share)/<name>*/(cmake|CMake)/ (U)
On systems supporting OS X Frameworks and Application Bundles
the following directories are searched for frameworks or bundles
containing a configuration file:
<prefix>/<name>.framework/Resources/ (A)
<prefix>/<name>.framework/Resources/CMake/ (A)
<prefix>/<name>.framework/Versions/*/Resources/ (A)
<prefix>/<name>.framework/Versions/*/Resources/CMake/ (A)
<prefix>/<name>.app/Contents/Resources/ (A)
<prefix>/<name>.app/Contents/Resources/CMake/ (A)
In all cases the <name> is treated as case-insensitive and cor‐
responds to any of the names specified (<package> or names given
by NAMES). Paths with lib/<arch> are enabled if
CMAKE_LIBRARY_ARCHITECTURE is set. If PATH_SUFFIXES is speci‐
fied the suffixes are appended to each (W) or (U) directory
entry one-by-one.
This set of directories is intended to work in cooperation with
projects that provide configuration files in their installation
trees. Directories above marked with (W) are intended for
installations on Windows where the prefix may point at the top
of an application's installation directory. Those marked with
(U) are intended for installations on UNIX platforms where the
prefix is shared by multiple packages. This is merely a conven‐
tion, so all (W) and (U) directories are still searched on all
platforms. Directories marked with (A) are intended for instal‐
lations on Apple platforms. The cmake variables
CMAKE_FIND_FRAMEWORK and CMAKE_FIND_APPBUNDLE determine the
order of preference as specified below.
The set of installation prefixes is constructed using the fol‐
lowing steps. If NO_DEFAULT_PATH is specified all NO_* options
are enabled.
1. Search paths specified in cmake-specific cache variables.
These are intended to be used on the command line with a
-DVAR=value. This can be skipped if NO_CMAKE_PATH is passed.
CMAKE_PREFIX_PATH
CMAKE_FRAMEWORK_PATH
CMAKE_APPBUNDLE_PATH
2. Search paths specified in cmake-specific environment vari‐
ables. These are intended to be set in the user's shell config‐
uration. This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed.
<package>_DIR
CMAKE_PREFIX_PATH
CMAKE_FRAMEWORK_PATH
CMAKE_APPBUNDLE_PATH
3. Search paths specified by the HINTS option. These should be
paths computed by system introspection, such as a hint provided
by the location of another item already found. Hard-coded
guesses should be specified with the PATHS option.
4. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is passed. Path entries
ending in "/bin" or "/sbin" are automatically converted to their
parent directories.
PATH
5. Search project build trees recently configured in a CMake
GUI. This can be skipped if NO_CMAKE_BUILDS_PATH is passed. It
is intended for the case when a user is building multiple depen‐
dent projects one after another.
6. Search paths stored in the CMake user package registry. This
can be skipped if NO_CMAKE_PACKAGE_REGISTRY is passed. On Win‐
dows a <package> may appear under registry key
HKEY_CURRENT_USER\Software\Kitware\CMake\Packages\<package>
as a REG_SZ value, with arbitrary name, that specifies the
directory containing the package configuration file. On UNIX
platforms a <package> may appear under the directory
~/.cmake/packages/<package>
as a file, with arbitrary name, whose content specifies the
directory containing the package configuration file. See the
export(PACKAGE) command to create user package registry entries
for project build trees.
7. Search cmake variables defined in the Platform files for the
current system. This can be skipped if NO_CMAKE_SYSTEM_PATH is
passed.
CMAKE_SYSTEM_PREFIX_PATH
CMAKE_SYSTEM_FRAMEWORK_PATH
CMAKE_SYSTEM_APPBUNDLE_PATH
8. Search paths stored in the CMake system package registry.
This can be skipped if NO_CMAKE_SYSTEM_PACKAGE_REGISTRY is
passed. On Windows a <package> may appear under registry key
HKEY_LOCAL_MACHINE\Software\Kitware\CMake\Packages\<package>
as a REG_SZ value, with arbitrary name, that specifies the
directory containing the package configuration file. There is
no system package registry on non-Windows platforms.
9. Search paths specified by the PATHS option. These are typi‐
cally hard-coded guesses.
On Darwin or systems supporting OS X Frameworks, the cmake vari‐
able CMAKE_FIND_FRAMEWORK can be set to empty or one of the
following:
"FIRST" - Try to find frameworks before standard
libraries or headers. This is the default on Darwin.
"LAST" - Try to find frameworks after standard
libraries or headers.
"ONLY" - Only try to find frameworks.
"NEVER" - Never try to find frameworks.
On Darwin or systems supporting OS X Application Bundles, the
cmake variable CMAKE_FIND_APPBUNDLE can be set to empty or one
of the following:
"FIRST" - Try to find application bundles before standard
programs. This is the default on Darwin.
"LAST" - Try to find application bundles after standard
programs.
"ONLY" - Only try to find application bundles.
"NEVER" - Never try to find application bundles.
The CMake variable CMAKE_FIND_ROOT_PATH specifies one or more
directories to be prepended to all other search directories.
This effectively "re-roots" the entire search under given loca‐
tions. By default it is empty. It is especially useful when
cross-compiling to point to the root directory of the target
environment and CMake will search there too. By default at first
the directories listed in CMAKE_FIND_ROOT_PATH and then the
non-rooted directories will be searched. The default behavior
can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_PACKAGE.
This behavior can be manually overridden on a per-call basis. By
using CMAKE_FIND_ROOT_PATH_BOTH the search order will be as
described above. If NO_CMAKE_FIND_ROOT_PATH is used then
CMAKE_FIND_ROOT_PATH will not be used. If
ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted direc‐
tories will be searched.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the
order by simply calling the command multiple times and using the
NO_* options:
find_package(<package> PATHS paths... NO_DEFAULT_PATH)
find_package(<package>)
Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.
Every non-REQUIRED find_package() call can be disabled by set‐
ting the variable CMAKE_DISABLE_FIND_PACKAGE_<package> to TRUE.
See the documentation for the CMAKE_DISABLE_FIND_PACKAGE_<pack‐
age> variable for more information.
When loading a find module or package configuration file
find_package defines variables to provide information about the
call arguments (and restores their original state before return‐
ing):
<package>_FIND_REQUIRED = true if REQUIRED option was given
<package>_FIND_QUIETLY = true if QUIET option was given
<package>_FIND_VERSION = full requested version string
<package>_FIND_VERSION_MAJOR = major version if requested, else 0
<package>_FIND_VERSION_MINOR = minor version if requested, else 0
<package>_FIND_VERSION_PATCH = patch version if requested, else 0
<package>_FIND_VERSION_TWEAK = tweak version if requested, else 0
<package>_FIND_VERSION_COUNT = number of version components, 0 to 4
<package>_FIND_VERSION_EXACT = true if EXACT option was given
<package>_FIND_COMPONENTS = list of requested components
<package>_FIND_REQUIRED_<c> = true if component <c> is required
false if component <c> is optional
In Module mode the loaded find module is responsible to honor
the request detailed by these variables; see the find module for
details. In Config mode find_package handles REQUIRED, QUIET,
and version options automatically but leaves it to the package
configuration file to handle components in a way that makes
sense for the package. The package configuration file may set
<package>_FOUND to false to tell find_package that component
requirements are not satisfied.
See the cmake_policy() command documentation for discussion of
the NO_POLICY_SCOPE option.
find_path
Find the directory containing a file.
find_path(<VAR> name1 [path1 path2 ...])
This is the short-hand signature for the command that is suffi‐
cient in many cases. It is the same as find_path(<VAR> name1
[PATHS path1 path2 ...])
find_path(
<VAR>
name | NAMES name1 [name2 ...]
[HINTS path1 [path2 ... ENV var]]
[PATHS path1 [path2 ... ENV var]]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[DOC "cache documentation string"]
[NO_DEFAULT_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_CMAKE_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_SYSTEM_PATH]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH]
)
This command is used to find a directory containing the named
file. A cache entry named by <VAR> is created to store the
result of this command. If the file in a directory is found the
result is stored in the variable and the search will not be
repeated unless the variable is cleared. If nothing is found,
the result will be <VAR>-NOTFOUND, and the search will be
attempted again the next time find_path is invoked with the same
variable. The name of the file in a directory that is searched
for is specified by the names listed after the NAMES argument.
Additional search locations can be specified after the PATHS
argument. If ENV var is found in the HINTS or PATHS section the
environment variable var will be read and converted from a sys‐
tem environment variable to a cmake style list of paths. For
example ENV PATH would be a way to list the system path vari‐
able. The argument after DOC will be used for the documentation
string in the cache. PATH_SUFFIXES specifies additional subdi‐
rectories to check below each search path.
If NO_DEFAULT_PATH is specified, then no additional paths are
added to the search. If NO_DEFAULT_PATH is not specified, the
search process is as follows:
1. Search paths specified in cmake-specific cache variables.
These are intended to be used on the command line with a
-DVAR=value. This can be skipped if NO_CMAKE_PATH is passed.
<prefix>/include for each <prefix> in CMAKE_PREFIX_PATH
CMAKE_INCLUDE_PATH
CMAKE_FRAMEWORK_PATH
2. Search paths specified in cmake-specific environment vari‐
ables. These are intended to be set in the user's shell config‐
uration. This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed.
<prefix>/include for each <prefix> in CMAKE_PREFIX_PATH
CMAKE_INCLUDE_PATH
CMAKE_FRAMEWORK_PATH
3. Search the paths specified by the HINTS option. These should
be paths computed by system introspection, such as a hint pro‐
vided by the location of another item already found. Hard-coded
guesses should be specified with the PATHS option.
4. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is an argument.
PATH
INCLUDE
5. Search cmake variables defined in the Platform files for the
current system. This can be skipped if NO_CMAKE_SYSTEM_PATH is
passed.
<prefix>/include for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH
CMAKE_SYSTEM_INCLUDE_PATH
CMAKE_SYSTEM_FRAMEWORK_PATH
6. Search the paths specified by the PATHS option or in the
short-hand version of the command. These are typically
hard-coded guesses.
On Darwin or systems supporting OS X Frameworks, the cmake vari‐
able CMAKE_FIND_FRAMEWORK can be set to empty or one of the
following:
"FIRST" - Try to find frameworks before standard
libraries or headers. This is the default on Darwin.
"LAST" - Try to find frameworks after standard
libraries or headers.
"ONLY" - Only try to find frameworks.
"NEVER" - Never try to find frameworks.
On Darwin or systems supporting OS X Application Bundles, the
cmake variable CMAKE_FIND_APPBUNDLE can be set to empty or one
of the following:
"FIRST" - Try to find application bundles before standard
programs. This is the default on Darwin.
"LAST" - Try to find application bundles after standard
programs.
"ONLY" - Only try to find application bundles.
"NEVER" - Never try to find application bundles.
The CMake variable CMAKE_FIND_ROOT_PATH specifies one or more
directories to be prepended to all other search directories.
This effectively "re-roots" the entire search under given loca‐
tions. By default it is empty. It is especially useful when
cross-compiling to point to the root directory of the target
environment and CMake will search there too. By default at first
the directories listed in CMAKE_FIND_ROOT_PATH and then the
non-rooted directories will be searched. The default behavior
can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_INCLUDE.
This behavior can be manually overridden on a per-call basis. By
using CMAKE_FIND_ROOT_PATH_BOTH the search order will be as
described above. If NO_CMAKE_FIND_ROOT_PATH is used then
CMAKE_FIND_ROOT_PATH will not be used. If
ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted direc‐
tories will be searched.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the
order by simply calling the command multiple times and using the
NO_* options:
find_path(<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
find_path(<VAR> NAMES name)
Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.
When searching for frameworks, if the file is specified as
A/b.h, then the framework search will look for A.framework/Head‐
ers/b.h. If that is found the path will be set to the path to
the framework. CMake will convert this to the correct -F option
to include the file.
find_program
Find an executable program.
find_program(<VAR> name1 [path1 path2 ...])
This is the short-hand signature for the command that is suffi‐
cient in many cases. It is the same as find_program(<VAR> name1
[PATHS path1 path2 ...])
find_program(
<VAR>
name | NAMES name1 [name2 ...]
[HINTS path1 [path2 ... ENV var]]
[PATHS path1 [path2 ... ENV var]]
[PATH_SUFFIXES suffix1 [suffix2 ...]]
[DOC "cache documentation string"]
[NO_DEFAULT_PATH]
[NO_CMAKE_ENVIRONMENT_PATH]
[NO_CMAKE_PATH]
[NO_SYSTEM_ENVIRONMENT_PATH]
[NO_CMAKE_SYSTEM_PATH]
[CMAKE_FIND_ROOT_PATH_BOTH |
ONLY_CMAKE_FIND_ROOT_PATH |
NO_CMAKE_FIND_ROOT_PATH]
)
This command is used to find a program. A cache entry named by
<VAR> is created to store the result of this command. If the
program is found the result is stored in the variable and the
search will not be repeated unless the variable is cleared. If
nothing is found, the result will be <VAR>-NOTFOUND, and the
search will be attempted again the next time find_program is
invoked with the same variable. The name of the program that is
searched for is specified by the names listed after the NAMES
argument. Additional search locations can be specified after
the PATHS argument. If ENV var is found in the HINTS or PATHS
section the environment variable var will be read and converted
from a system environment variable to a cmake style list of
paths. For example ENV PATH would be a way to list the system
path variable. The argument after DOC will be used for the docu‐
mentation string in the cache. PATH_SUFFIXES specifies addi‐
tional subdirectories to check below each search path.
If NO_DEFAULT_PATH is specified, then no additional paths are
added to the search. If NO_DEFAULT_PATH is not specified, the
search process is as follows:
1. Search paths specified in cmake-specific cache variables.
These are intended to be used on the command line with a
-DVAR=value. This can be skipped if NO_CMAKE_PATH is passed.
<prefix>/[s]bin for each <prefix> in CMAKE_PREFIX_PATH
CMAKE_PROGRAM_PATH
CMAKE_APPBUNDLE_PATH
2. Search paths specified in cmake-specific environment vari‐
ables. These are intended to be set in the user's shell config‐
uration. This can be skipped if NO_CMAKE_ENVIRONMENT_PATH is
passed.
<prefix>/[s]bin for each <prefix> in CMAKE_PREFIX_PATH
CMAKE_PROGRAM_PATH
CMAKE_APPBUNDLE_PATH
3. Search the paths specified by the HINTS option. These should
be paths computed by system introspection, such as a hint pro‐
vided by the location of another item already found. Hard-coded
guesses should be specified with the PATHS option.
4. Search the standard system environment variables. This can be
skipped if NO_SYSTEM_ENVIRONMENT_PATH is an argument.
PATH
5. Search cmake variables defined in the Platform files for the
current system. This can be skipped if NO_CMAKE_SYSTEM_PATH is
passed.
<prefix>/[s]bin for each <prefix> in CMAKE_SYSTEM_PREFIX_PATH
CMAKE_SYSTEM_PROGRAM_PATH
CMAKE_SYSTEM_APPBUNDLE_PATH
6. Search the paths specified by the PATHS option or in the
short-hand version of the command. These are typically
hard-coded guesses.
On Darwin or systems supporting OS X Frameworks, the cmake vari‐
able CMAKE_FIND_FRAMEWORK can be set to empty or one of the
following:
"FIRST" - Try to find frameworks before standard
libraries or headers. This is the default on Darwin.
"LAST" - Try to find frameworks after standard
libraries or headers.
"ONLY" - Only try to find frameworks.
"NEVER" - Never try to find frameworks.
On Darwin or systems supporting OS X Application Bundles, the
cmake variable CMAKE_FIND_APPBUNDLE can be set to empty or one
of the following:
"FIRST" - Try to find application bundles before standard
programs. This is the default on Darwin.
"LAST" - Try to find application bundles after standard
programs.
"ONLY" - Only try to find application bundles.
"NEVER" - Never try to find application bundles.
The CMake variable CMAKE_FIND_ROOT_PATH specifies one or more
directories to be prepended to all other search directories.
This effectively "re-roots" the entire search under given loca‐
tions. By default it is empty. It is especially useful when
cross-compiling to point to the root directory of the target
environment and CMake will search there too. By default at first
the directories listed in CMAKE_FIND_ROOT_PATH and then the
non-rooted directories will be searched. The default behavior
can be adjusted by setting CMAKE_FIND_ROOT_PATH_MODE_PROGRAM.
This behavior can be manually overridden on a per-call basis. By
using CMAKE_FIND_ROOT_PATH_BOTH the search order will be as
described above. If NO_CMAKE_FIND_ROOT_PATH is used then
CMAKE_FIND_ROOT_PATH will not be used. If
ONLY_CMAKE_FIND_ROOT_PATH is used then only the re-rooted direc‐
tories will be searched.
The default search order is designed to be most-specific to
least-specific for common use cases. Projects may override the
order by simply calling the command multiple times and using the
NO_* options:
find_program(<VAR> NAMES name PATHS paths... NO_DEFAULT_PATH)
find_program(<VAR> NAMES name)
Once one of the calls succeeds the result variable will be set
and stored in the cache so that no call will search again.
fltk_wrap_ui
Create FLTK user interfaces Wrappers.
fltk_wrap_ui(resultingLibraryName source1
source2 ... sourceN )
Produce .h and .cxx files for all the .fl and .fld files listed.
The resulting .h and .cxx files will be added to a variable
named resultingLibraryName_FLTK_UI_SRCS which should be added to
your library.
foreach
Evaluate a group of commands for each value in a list.
foreach(loop_var arg1 arg2 ...)
COMMAND1(ARGS ...)
COMMAND2(ARGS ...)
...
endforeach(loop_var)
All commands between foreach and the matching endforeach are
recorded without being invoked. Once the endforeach is evalu‐
ated, the recorded list of commands is invoked once for each
argument listed in the original foreach command. Before each
iteration of the loop "${loop_var}" will be set as a variable
with the current value in the list.
foreach(loop_var RANGE total)
foreach(loop_var RANGE start stop [step])
Foreach can also iterate over a generated range of numbers.
There are three types of this iteration:
* When specifying single number, the range will have elements 0
to "total".
* When specifying two numbers, the range will have elements from
the first number to the second number.
* The third optional number is the increment used to iterate
from the first number to the second number.
foreach(loop_var IN [LISTS [list1 [...]]]
[ITEMS [item1 [...]]])
Iterates over a precise list of items. The LISTS option names
list-valued variables to be traversed, including empty elements
(an empty string is a zero-length list). The ITEMS option ends
argument parsing and includes all arguments following it in the
iteration.
function
Start recording a function for later invocation as a command.
function(<name> [arg1 [arg2 [arg3 ...]]])
COMMAND1(ARGS ...)
COMMAND2(ARGS ...)
...
endfunction(<name>)
Define a function named <name> that takes arguments named arg1
arg2 arg3 (...). Commands listed after function, but before the
matching endfunction, are not invoked until the function is
invoked. When it is invoked, the commands recorded in the func‐
tion are first modified by replacing formal parameters (${arg1})
with the arguments passed, and then invoked as normal commands.
In addition to referencing the formal parameters you can refer‐
ence the variable ARGC which will be set to the number of argu‐
ments passed into the function as well as ARGV0 ARGV1 ARGV2 ...
which will have the actual values of the arguments passed in.
This facilitates creating functions with optional arguments.
Additionally ARGV holds the list of all arguments given to the
function and ARGN holds the list of argument past the last
expected argument.
See the cmake_policy() command documentation for the behavior of
policies inside functions.
get_cmake_property
Get a property of the CMake instance.
get_cmake_property(VAR property)
Get a property from the CMake instance. The value of the prop‐
erty is stored in the variable VAR. If the property is not
found, VAR will be set to "NOTFOUND". Some supported properties
include: VARIABLES, CACHE_VARIABLES, COMMANDS, MACROS, and COM‐
PONENTS.
See also the more general get_property() command.
get_directory_property
Get a property of DIRECTORY scope.
get_directory_property(<variable> [DIRECTORY <dir>] <prop-name>)
Store a property of directory scope in the named variable. If
the property is not defined the empty-string is returned. The
DIRECTORY argument specifies another directory from which to
retrieve the property value. The specified directory must have
already been traversed by CMake.
get_directory_property(<variable> [DIRECTORY <dir>]
DEFINITION <var-name>)
Get a variable definition from a directory. This form is useful
to get a variable definition from another directory.
See also the more general get_property() command.
get_filename_component
Get a specific component of a full filename.
get_filename_component(<VAR> FileName
PATH|ABSOLUTE|NAME|EXT|NAME_WE|REALPATH
[CACHE])
Set <VAR> to be the path (PATH), file name (NAME), file exten‐
sion (EXT), file name without extension (NAME_WE) of FileName,
the full path (ABSOLUTE), or the full path with all symlinks
resolved (REALPATH). Note that the path is converted to Unix
slashes format and has no trailing slashes. The longest file
extension is always considered. If the optional CACHE argument
is specified, the result variable is added to the cache.
get_filename_component(<VAR> FileName
PROGRAM [PROGRAM_ARGS <ARG_VAR>]
[CACHE])
The program in FileName will be found in the system search path
or left as a full path. If PROGRAM_ARGS is present with PRO‐
GRAM, then any command-line arguments present in the FileName
string are split from the program name and stored in <ARG_VAR>.
This is used to separate a program name from its arguments in a
command line string.
get_property
Get a property.
get_property(<variable>
<GLOBAL |
DIRECTORY [dir] |
TARGET <target> |
SOURCE <source> |
TEST <test> |
CACHE <entry> |
VARIABLE>
PROPERTY <name>
[SET | DEFINED | BRIEF_DOCS | FULL_DOCS])
Get one property from one object in a scope. The first argument
specifies the variable in which to store the result. The second
argument determines the scope from which to get the property.
It must be one of the following:
GLOBAL scope is unique and does not accept a name.
DIRECTORY scope defaults to the current directory but another
directory (already processed by CMake) may be named by full or
relative path.
TARGET scope must name one existing target.
SOURCE scope must name one source file.
TEST scope must name one existing test.
CACHE scope must name one cache entry.
VARIABLE scope is unique and does not accept a name.
The required PROPERTY option is immediately followed by the name
of the property to get. If the property is not set an empty
value is returned. If the SET option is given the variable is
set to a boolean value indicating whether the property has been
set. If the DEFINED option is given the variable is set to a
boolean value indicating whether the property has been defined
such as with define_property. If BRIEF_DOCS or FULL_DOCS is
given then the variable is set to a string containing documenta‐
tion for the requested property. If documentation is requested
for a property that has not been defined NOTFOUND is returned.
get_source_file_property
Get a property for a source file.
get_source_file_property(VAR file property)
Get a property from a source file. The value of the property is
stored in the variable VAR. If the property is not found, VAR
will be set to "NOTFOUND". Use set_source_files_properties to
set property values. Source file properties usually control how
the file is built. One property that is always there is LOCATION
See also the more general get_property() command.
get_target_property
Get a property from a target.
get_target_property(VAR target property)
Get a property from a target. The value of the property is
stored in the variable VAR. If the property is not found, VAR
will be set to "NOTFOUND". Use set_target_properties to set
property values. Properties are usually used to control how a
target is built, but some query the target instead. This com‐
mand can get properties for any target so far created. The tar‐
gets do not need to be in the current CMakeLists.txt file.
See also the more general get_property() command.
get_test_property
Get a property of the test.
get_test_property(test property VAR)
Get a property from the Test. The value of the property is
stored in the variable VAR. If the property is not found, VAR
will be set to "NOTFOUND". For a list of standard properties you
can type cmake --help-property-list
See also the more general get_property() command.
if Conditionally execute a group of commands.
if(expression)
# then section.
COMMAND1(ARGS ...)
COMMAND2(ARGS ...)
...
elseif(expression2)
# elseif section.
COMMAND1(ARGS ...)
COMMAND2(ARGS ...)
...
else(expression)
# else section.
COMMAND1(ARGS ...)
COMMAND2(ARGS ...)
...
endif(expression)
Evaluates the given expression. If the result is true, the com‐
mands in the THEN section are invoked. Otherwise, the commands
in the else section are invoked. The elseif and else sections
are optional. You may have multiple elseif clauses. Note that
the expression in the else and endif clause is optional. Long
expressions can be used and there is a traditional order of
precedence. Parenthetical expressions are evaluated first fol‐
lowed by unary operators such as EXISTS, COMMAND, and DEFINED.
Then any EQUAL, LESS, GREATER, STRLESS, STRGREATER, STREQUAL,
MATCHES will be evaluated. Then NOT operators and finally AND,
OR operators will be evaluated. Possible expressions are:
if(<constant>)
True if the constant is 1, ON, YES, TRUE, Y, or a non-zero num‐
ber. False if the constant is 0, OFF, NO, FALSE, N, IGNORE, "",
or ends in the suffix '-NOTFOUND'. Named boolean constants are
case-insensitive. If the argument is not one of these con‐
stants, it is treated as a variable:
if(<variable>)
True if the variable is defined to a value that is not a false
constant. False otherwise. (Note macro arguments are not vari‐
ables.)
if(NOT <expression>)
True if the expression is not true.
if(<expr1> AND <expr2>)
True if both expressions would be considered true individually.
if(<expr1> OR <expr2>)
True if either expression would be considered true individually.
if(COMMAND command-name)
True if the given name is a command, macro or function that can
be invoked.
if(POLICY policy-id)
True if the given name is an existing policy (of the form
CMP<NNNN>).
if(TARGET target-name)
True if the given name is an existing target, built or imported.
if(EXISTS file-name)
if(EXISTS directory-name)
True if the named file or directory exists. Behavior is
well-defined only for full paths.
if(file1 IS_NEWER_THAN file2)
True if file1 is newer than file2 or if one of the two files
doesn't exist. Behavior is well-defined only for full paths.
if(IS_DIRECTORY directory-name)
True if the given name is a directory. Behavior is well-defined
only for full paths.
if(IS_SYMLINK file-name)
True if the given name is a symbolic link. Behavior is
well-defined only for full paths.
if(IS_ABSOLUTE path)
True if the given path is an absolute path.
if(<variable|string> MATCHES regex)
True if the given string or variable's value matches the given
regular expression.
if(<variable|string> LESS <variable|string>)
if(<variable|string> GREATER <variable|string>)
if(<variable|string> EQUAL <variable|string>)
True if the given string or variable's value is a valid number
and the inequality or equality is true.
if(<variable|string> STRLESS <variable|string>)
if(<variable|string> STRGREATER <variable|string>)
if(<variable|string> STREQUAL <variable|string>)
True if the given string or variable's value is lexicographi‐
cally less (or greater, or equal) than the string or variable on
the right.
if(<variable|string> VERSION_LESS <variable|string>)
if(<variable|string> VERSION_EQUAL <variable|string>)
if(<variable|string> VERSION_GREATER <variable|string>)
Component-wise integer version number comparison (version format
is major[.minor[.patch[.tweak]]]).
if(DEFINED <variable>)
True if the given variable is defined. It does not matter if the
variable is true or false just if it has been set.
if((expression) AND (expression OR (expression)))
The expressions inside the parenthesis are evaluated first and
then the remaining expression is evaluated as in the previous
examples. Where there are nested parenthesis the innermost are
evaluated as part of evaluating the expression that contains
them.
The if command was written very early in CMake's history, pre‐
dating the ${} variable evaluation syntax, and for convenience
evaluates variables named by its arguments as shown in the above
signatures. Note that normal variable evaluation with ${}
applies before the if command even receives the arguments.
Therefore code like
set(var1 OFF)
set(var2 "var1")
if(${var2})
appears to the if command as
if(var1)
and is evaluated according to the if(<variable>) case documented
above. The result is OFF which is false. However, if we remove
the ${} from the example then the command sees
if(var2)
which is true because var2 is defined to "var1" which is not a
false constant.
Automatic evaluation applies in the other cases whenever the
above-documented signature accepts <variable|string>:
1) The left hand argument to MATCHES is first checked to see if
it is a defined variable, if so the variable's value is used,
otherwise the original value is used.
2) If the left hand argument to MATCHES is missing it returns
false without error
3) Both left and right hand arguments to LESS GREATER EQUAL are
independently tested to see if they are defined variables, if so
their defined values are used otherwise the original value is
used.
4) Both left and right hand arguments to STRLESS STREQUAL STR‐
GREATER are independently tested to see if they are defined
variables, if so their defined values are used otherwise the
original value is used.
5) Both left and right hand argumemnts to VERSION_LESS VER‐
SION_EQUAL VERSION_GREATER are independently tested to see if
they are defined variables, if so their defined values are used
otherwise the original value is used.
6) The right hand argument to NOT is tested to see if it is a
boolean constant, if so the value is used, otherwise it is
assumed to be a variable and it is dereferenced.
7) The left and right hand arguments to AND OR are independently
tested to see if they are boolean constants, if so they are used
as such, otherwise they are assumed to be variables and are
dereferenced.
include
Read CMake listfile code from the given file.
include(<file|module> [OPTIONAL] [RESULT_VARIABLE <VAR>]
[NO_POLICY_SCOPE])
Reads CMake listfile code from the given file. Commands in the
file are processed immediately as if they were written in place
of the include command. If OPTIONAL is present, then no error
is raised if the file does not exist. If RESULT_VARIABLE is
given the variable will be set to the full filename which has
been included or NOTFOUND if it failed.
If a module is specified instead of a file, the file with name
<modulename>.cmake is searched first in CMAKE_MODULE_PATH, then
in the CMake module directory. There is one exception to this:
if the file which calls include() is located itself in the CMake
module directory, then first the CMake module directory is
searched and CMAKE_MODULE_PATH afterwards. See also policy
CMP0017.
See the cmake_policy() command documentation for discussion of
the NO_POLICY_SCOPE option.
include_directories
Add include directories to the build.
include_directories([AFTER|BEFORE] [SYSTEM] dir1 dir2 ...)
Add the given directories to those the compiler uses to search
for include files. These directories are added to the directory
property INCLUDE_DIRECTORIES for the current CMakeLists file.
They are also added to the target property INCLUDE_DIRECTORIES
for each target in the current CMakeLists file. The target prop‐
erty values are the ones used by the generators.
By default the directories are appended onto the current list of
directories. This default behavior can be changed by setting
CMAKE_INCLUDE_DIRECTORIES_BEFORE to ON. By using AFTER or BEFORE
explicitly, you can select between appending and prepending,
independent of the default. If the SYSTEM option is given, the
compiler will be told the directories are meant as system
include directories on some platforms.
include_external_msproject
Include an external Microsoft project file in a workspace.
include_external_msproject(projectname location
[TYPE projectTypeGUID]
[GUID projectGUID]
[PLATFORM platformName]
dep1 dep2 ...)
Includes an external Microsoft project in the generated
workspace file. Currently does nothing on UNIX. This will cre‐
ate a target named [projectname]. This can be used in the
add_dependencies command to make things depend on the external
project.
TYPE, GUID and PLATFORM are optional parameters that allow one
to specify the type of project, id (GUID) of the project and the
name of the target platform. This is useful for projects
requiring values other than the default (e.g. WIX projects).
These options are not supported by the Visual Studio 6 genera‐
tor.
include_regular_expression
Set the regular expression used for dependency checking.
include_regular_expression(regex_match [regex_complain])
Set the regular expressions used in dependency checking. Only
files matching regex_match will be traced as dependencies. Only
files matching regex_complain will generate warnings if they
cannot be found (standard header paths are not searched). The
defaults are:
regex_match = "^.*$" (match everything)
regex_complain = "^$" (match empty string only)
install
Specify rules to run at install time.
This command generates installation rules for a project. Rules
specified by calls to this command within a source directory are
executed in order during installation. The order across direc‐
tories is not defined.
There are multiple signatures for this command. Some of them
define installation properties for files and targets. Proper‐
ties common to multiple signatures are covered here but they are
valid only for signatures that specify them.
DESTINATION arguments specify the directory on disk to which a
file will be installed. If a full path (with a leading slash or
drive letter) is given it is used directly. If a relative path
is given it is interpreted relative to the value of
CMAKE_INSTALL_PREFIX.
PERMISSIONS arguments specify permissions for installed files.
Valid permissions are OWNER_READ, OWNER_WRITE, OWNER_EXECUTE,
GROUP_READ, GROUP_WRITE, GROUP_EXECUTE, WORLD_READ, WORLD_WRITE,
WORLD_EXECUTE, SETUID, and SETGID. Permissions that do not make
sense on certain platforms are ignored on those platforms.
The CONFIGURATIONS argument specifies a list of build configura‐
tions for which the install rule applies (Debug, Release, etc.).
The COMPONENT argument specifies an installation component name
with which the install rule is associated, such as "runtime" or
"development". During component-specific installation only
install rules associated with the given component name will be
executed. During a full installation all components are
installed. If COMPONENT is not provided a default component
"Unspecified" is created. The default component name may be con‐
trolled with the CMAKE_INSTALL_DEFAULT_COMPONENT_NAME variable.
The RENAME argument specifies a name for an installed file that
may be different from the original file. Renaming is allowed
only when a single file is installed by the command.
The OPTIONAL argument specifies that it is not an error if the
file to be installed does not exist.
The TARGETS signature:
install(TARGETS targets... [EXPORT <export-name>]
[[ARCHIVE|LIBRARY|RUNTIME|FRAMEWORK|BUNDLE|
PRIVATE_HEADER|PUBLIC_HEADER|RESOURCE]
[DESTINATION <dir>]
[PERMISSIONS permissions...]
[CONFIGURATIONS [Debug|Release|...]]
[COMPONENT <component>]
[OPTIONAL] [NAMELINK_ONLY|NAMELINK_SKIP]
] [...])
The TARGETS form specifies rules for installing targets from a
project. There are five kinds of target files that may be
installed: ARCHIVE, LIBRARY, RUNTIME, FRAMEWORK, and BUNDLE.
Executables are treated as RUNTIME targets, except that those
marked with the MACOSX_BUNDLE property are treated as BUNDLE
targets on OS X. Static libraries are always treated as ARCHIVE
targets. Module libraries are always treated as LIBRARY targets.
For non-DLL platforms shared libraries are treated as LIBRARY
targets, except that those marked with the FRAMEWORK property
are treated as FRAMEWORK targets on OS X. For DLL platforms the
DLL part of a shared library is treated as a RUNTIME target and
the corresponding import library is treated as an ARCHIVE tar‐
get. All Windows-based systems including Cygwin are DLL plat‐
forms. The ARCHIVE, LIBRARY, RUNTIME, and FRAMEWORK arguments
change the type of target to which the subsequent properties
apply. If none is given the installation properties apply to
all target types. If only one is given then only targets of
that type will be installed (which can be used to install just a
DLL or just an import library).
The PRIVATE_HEADER, PUBLIC_HEADER, and RESOURCE arguments cause
subsequent properties to be applied to installing a FRAMEWORK
shared library target's associated files on non-Apple platforms.
Rules defined by these arguments are ignored on Apple platforms
because the associated files are installed into the appropriate
locations inside the framework folder. See documentation of the
PRIVATE_HEADER, PUBLIC_HEADER, and RESOURCE target properties
for details.
Either NAMELINK_ONLY or NAMELINK_SKIP may be specified as a
LIBRARY option. On some platforms a versioned shared library
has a symbolic link such as
lib<name>.so -> lib<name>.so.1
where "lib<name>.so.1" is the soname of the library and
"lib<name>.so" is a "namelink" allowing linkers to find the
library when given "-l<name>". The NAMELINK_ONLY option causes
installation of only the namelink when a library target is
installed. The NAMELINK_SKIP option causes installation of
library files other than the namelink when a library target is
installed. When neither option is given both portions are
installed. On platforms where versioned shared libraries do not
have namelinks or when a library is not versioned the
NAMELINK_SKIP option installs the library and the NAMELINK_ONLY
option installs nothing. See the VERSION and SOVERSION target
properties for details on creating versioned shared libraries.
One or more groups of properties may be specified in a single
call to the TARGETS form of this command. A target may be
installed more than once to different locations. Consider hypo‐
thetical targets "myExe", "mySharedLib", and "myStaticLib". The
code
install(TARGETS myExe mySharedLib myStaticLib
RUNTIME DESTINATION bin
LIBRARY DESTINATION lib
ARCHIVE DESTINATION lib/static)
install(TARGETS mySharedLib DESTINATION /some/full/path)
will install myExe to <prefix>/bin and myStaticLib to <pre‐
fix>/lib/static. On non-DLL platforms mySharedLib will be
installed to <prefix>/lib and /some/full/path. On DLL platforms
the mySharedLib DLL will be installed to <prefix>/bin and
/some/full/path and its import library will be installed to
<prefix>/lib/static and /some/full/path.
The EXPORT option associates the installed target files with an
export called <export-name>. It must appear before any RUNTIME,
LIBRARY, or ARCHIVE options. To actually install the export
file itself, call install(EXPORT). See documentation of the
install(EXPORT ...) signature below for details.
Installing a target with EXCLUDE_FROM_ALL set to true has unde‐
fined behavior.
The FILES signature:
install(FILES files... DESTINATION <dir>
[PERMISSIONS permissions...]
[CONFIGURATIONS [Debug|Release|...]]
[COMPONENT <component>]
[RENAME <name>] [OPTIONAL])
The FILES form specifies rules for installing files for a
project. File names given as relative paths are interpreted
with respect to the current source directory. Files installed
by this form are by default given permissions OWNER_WRITE,
OWNER_READ, GROUP_READ, and WORLD_READ if no PERMISSIONS argu‐
ment is given.
The PROGRAMS signature:
install(PROGRAMS files... DESTINATION <dir>
[PERMISSIONS permissions...]
[CONFIGURATIONS [Debug|Release|...]]
[COMPONENT <component>]
[RENAME <name>] [OPTIONAL])
The PROGRAMS form is identical to the FILES form except that the
default permissions for the installed file also include
OWNER_EXECUTE, GROUP_EXECUTE, and WORLD_EXECUTE. This form is
intended to install programs that are not targets, such as shell
scripts. Use the TARGETS form to install targets built within
the project.
The DIRECTORY signature:
install(DIRECTORY dirs... DESTINATION <dir>
[FILE_PERMISSIONS permissions...]
[DIRECTORY_PERMISSIONS permissions...]
[USE_SOURCE_PERMISSIONS] [OPTIONAL]
[CONFIGURATIONS [Debug|Release|...]]
[COMPONENT <component>] [FILES_MATCHING]
[[PATTERN <pattern> | REGEX <regex>]
[EXCLUDE] [PERMISSIONS permissions...]] [...])
The DIRECTORY form installs contents of one or more directories
to a given destination. The directory structure is copied ver‐
batim to the destination. The last component of each directory
name is appended to the destination directory but a trailing
slash may be used to avoid this because it leaves the last com‐
ponent empty. Directory names given as relative paths are
interpreted with respect to the current source directory. If no
input directory names are given the destination directory will
be created but nothing will be installed into it. The FILE_PER‐
MISSIONS and DIRECTORY_PERMISSIONS options specify permissions
given to files and directories in the destination. If
USE_SOURCE_PERMISSIONS is specified and FILE_PERMISSIONS is not,
file permissions will be copied from the source directory struc‐
ture. If no permissions are specified files will be given the
default permissions specified in the FILES form of the command,
and the directories will be given the default permissions speci‐
fied in the PROGRAMS form of the command.
Installation of directories may be controlled with fine granu‐
larity using the PATTERN or REGEX options. These "match"
options specify a globbing pattern or regular expression to
match directories or files encountered within input directories.
They may be used to apply certain options (see below) to a sub‐
set of the files and directories encountered. The full path to
each input file or directory (with forward slashes) is matched
against the expression. A PATTERN will match only complete file
names: the portion of the full path matching the pattern must
occur at the end of the file name and be preceded by a slash. A
REGEX will match any portion of the full path but it may use '/'
and '$' to simulate the PATTERN behavior. By default all files
and directories are installed whether or not they are matched.
The FILES_MATCHING option may be given before the first match
option to disable installation of files (but not directories)
not matched by any expression. For example, the code
install(DIRECTORY src/ DESTINATION include/myproj
FILES_MATCHING PATTERN "*.h")
will extract and install header files from a source tree.
Some options may follow a PATTERN or REGEX expression and are
applied only to files or directories matching them. The EXCLUDE
option will skip the matched file or directory. The PERMISSIONS
option overrides the permissions setting for the matched file or
directory. For example the code
install(DIRECTORY icons scripts/ DESTINATION share/myproj
PATTERN "CVS" EXCLUDE
PATTERN "scripts/*"
PERMISSIONS OWNER_EXECUTE OWNER_WRITE OWNER_READ
GROUP_EXECUTE GROUP_READ)
will install the icons directory to share/myproj/icons and the
scripts directory to share/myproj. The icons will get default
file permissions, the scripts will be given specific permis‐
sions, and any CVS directories will be excluded.
The SCRIPT and CODE signature:
install([[SCRIPT <file>] [CODE <code>]] [...])
The SCRIPT form will invoke the given CMake script files during
installation. If the script file name is a relative path it
will be interpreted with respect to the current source direc‐
tory. The CODE form will invoke the given CMake code during
installation. Code is specified as a single argument inside a
double-quoted string. For example, the code
install(CODE "MESSAGE(\"Sample install message.\")")
will print a message during installation.
The EXPORT signature:
install(EXPORT <export-name> DESTINATION <dir>
[NAMESPACE <namespace>] [FILE <name>.cmake]
[PERMISSIONS permissions...]
[CONFIGURATIONS [Debug|Release|...]]
[COMPONENT <component>])
The EXPORT form generates and installs a CMake file containing
code to import targets from the installation tree into another
project. Target installations are associated with the export
<export-name> using the EXPORT option of the install(TARGETS
...) signature documented above. The NAMESPACE option will
prepend <namespace> to the target names as they are written to
the import file. By default the generated file will be called
<export-name>.cmake but the FILE option may be used to specify a
different name. The value given to the FILE option must be a
file name with the ".cmake" extension. If a CONFIGURATIONS
option is given then the file will only be installed when one of
the named configurations is installed. Additionally, the gener‐
ated import file will reference only the matching target config‐
urations. If a COMPONENT option is specified that does not
match that given to the targets associated with <export-name>
the behavior is undefined. If a library target is included in
the export but a target to which it links is not included the
behavior is unspecified.
The EXPORT form is useful to help outside projects use targets
built and installed by the current project. For example, the
code
install(TARGETS myexe EXPORT myproj DESTINATION bin)
install(EXPORT myproj NAMESPACE mp_ DESTINATION lib/myproj)
will install the executable myexe to <prefix>/bin and code to
import it in the file "<prefix>/lib/myproj/myproj.cmake". An
outside project may load this file with the include command and
reference the myexe executable from the installation tree using
the imported target name mp_myexe as if the target were built in
its own tree.
NOTE: This command supercedes the INSTALL_TARGETS command and
the target properties PRE_INSTALL_SCRIPT and
POST_INSTALL_SCRIPT. It also replaces the FILES forms of the
INSTALL_FILES and INSTALL_PROGRAMS commands. The processing
order of these install rules relative to those generated by
INSTALL_TARGETS, INSTALL_FILES, and INSTALL_PROGRAMS commands is
not defined.
link_directories
Specify directories in which the linker will look for libraries.
link_directories(directory1 directory2 ...)
Specify the paths in which the linker should search for
libraries. The command will apply only to targets created after
it is called. For historical reasons, relative paths given to
this command are passed to the linker unchanged (unlike many
CMake commands which interpret them relative to the current
source directory).
Note that this command is rarely necessary. Library locations
returned by find_package() and find_library() are absolute
paths. Pass these absolute library file paths directly to the
target_link_libraries() command. CMake will ensure the linker
finds them.
list List operations.
list(LENGTH <list> <output variable>)
list(GET <list> <element index> [<element index> ...]
<output variable>)
list(APPEND <list> <element> [<element> ...])
list(FIND <list> <value> <output variable>)
list(INSERT <list> <element_index> <element> [<element> ...])
list(REMOVE_ITEM <list> <value> [<value> ...])
list(REMOVE_AT <list> <index> [<index> ...])
list(REMOVE_DUPLICATES <list>)
list(REVERSE <list>)
list(SORT <list>)
LENGTH will return a given list's length.
GET will return list of elements specified by indices from the
list.
APPEND will append elements to the list.
FIND will return the index of the element specified in the list
or -1 if it wasn't found.
INSERT will insert elements to the list to the specified loca‐
tion.
REMOVE_AT and REMOVE_ITEM will remove items from the list. The
difference is that REMOVE_ITEM will remove the given items,
while REMOVE_AT will remove the items at the given indices.
REMOVE_DUPLICATES will remove duplicated items in the list.
REVERSE reverses the contents of the list in-place.
SORT sorts the list in-place alphabetically.
The list subcommands APPEND, INSERT, REMOVE_AT, REMOVE_ITEM,
REMOVE_DUPLICATES, REVERSE and SORT may create new values for
the list within the current CMake variable scope. Similar to the
SET command, the LIST command creates new variable values in the
current scope, even if the list itself is actually defined in a
parent scope. To propagate the results of these operations
upwards, use SET with PARENT_SCOPE, SET with CACHE INTERNAL, or
some other means of value propagation.
NOTES: A list in cmake is a ; separated group of strings. To
create a list the set command can be used. For example, set(var
a b c d e) creates a list with a;b;c;d;e, and set(var "a b c d
e") creates a string or a list with one item in it.
When specifying index values, if <element index> is 0 or
greater, it is indexed from the beginning of the list, with 0
representing the first list element. If <element index> is -1 or
lesser, it is indexed from the end of the list, with -1 repre‐
senting the last list element. Be careful when counting with
negative indices: they do not start from 0. -0 is equivalent to
0, the first list element.
load_cache
Load in the values from another project's CMake cache.
load_cache(pathToCacheFile READ_WITH_PREFIX
prefix entry1...)
Read the cache and store the requested entries in variables with
their name prefixed with the given prefix. This only reads the
values, and does not create entries in the local project's
cache.
load_cache(pathToCacheFile [EXCLUDE entry1...]
[INCLUDE_INTERNALS entry1...])
Load in the values from another cache and store them in the
local project's cache as internal entries. This is useful for a
project that depends on another project built in a different
tree. EXCLUDE option can be used to provide a list of entries
to be excluded. INCLUDE_INTERNALS can be used to provide a list
of internal entries to be included. Normally, no internal
entries are brought in. Use of this form of the command is
strongly discouraged, but it is provided for backward compati‐
bility.
load_command
Load a command into a running CMake.
load_command(COMMAND_NAME <loc1> [loc2 ...])
The given locations are searched for a library whose name is
cmCOMMAND_NAME. If found, it is loaded as a module and the com‐
mand is added to the set of available CMake commands. Usually,
TRY_COMPILE is used before this command to compile the module.
If the command is successfully loaded a variable named
CMAKE_LOADED_COMMAND_<COMMAND_NAME>
will be set to the full path of the module that was loaded.
Otherwise the variable will not be set.
macro Start recording a macro for later invocation as a command.
macro(<name> [arg1 [arg2 [arg3 ...]]])
COMMAND1(ARGS ...)
COMMAND2(ARGS ...)
...
endmacro(<name>)
Define a macro named <name> that takes arguments named arg1 arg2
arg3 (...). Commands listed after macro, but before the match‐
ing endmacro, are not invoked until the macro is invoked. When
it is invoked, the commands recorded in the macro are first mod‐
ified by replacing formal parameters (${arg1}) with the argu‐
ments passed, and then invoked as normal commands. In addition
to referencing the formal parameters you can reference the val‐
ues ${ARGC} which will be set to the number of arguments passed
into the function as well as ${ARGV0} ${ARGV1} ${ARGV2} ...
which will have the actual values of the arguments passed in.
This facilitates creating macros with optional arguments. Addi‐
tionally ${ARGV} holds the list of all arguments given to the
macro and ${ARGN} holds the list of argument past the last
expected argument. Note that the parameters to a macro and val‐
ues such as ARGN are not variables in the usual CMake sense.
They are string replacements much like the c preprocessor would
do with a macro. If you want true CMake variables you should
look at the function command.
See the cmake_policy() command documentation for the behavior of
policies inside macros.
mark_as_advanced
Mark cmake cached variables as advanced.
mark_as_advanced([CLEAR|FORCE] VAR VAR2 VAR...)
Mark the named cached variables as advanced. An advanced vari‐
able will not be displayed in any of the cmake GUIs unless the
show advanced option is on. If CLEAR is the first argument
advanced variables are changed back to unadvanced. If FORCE is
the first argument, then the variable is made advanced. If nei‐
ther FORCE nor CLEAR is specified, new values will be marked as
advanced, but if the variable already has an
advanced/non-advanced state, it will not be changed.
It does nothing in script mode.
math Mathematical expressions.
math(EXPR <output variable> <math expression>)
EXPR evaluates mathematical expression and return result in the
output variable. Example mathematical expression is '5 * ( 10 +
13 )'. Supported operators are + - * / % | & ^ ~ << >> * / %.
They have the same meaning as they do in c code.
message
Display a message to the user.
message([STATUS|WARNING|AUTHOR_WARNING|FATAL_ERROR|SEND_ERROR]
"message to display" ...)
The optional keyword determines the type of message:
(none) = Important information
STATUS = Incidental information
WARNING = CMake Warning, continue processing
AUTHOR_WARNING = CMake Warning (dev), continue processing
SEND_ERROR = CMake Error, continue but skip generation
FATAL_ERROR = CMake Error, stop all processing
The CMake command-line tool displays STATUS messages on stdout
and all other message types on stderr. The CMake GUI displays
all messages in its log area. The interactive dialogs (ccmake
and CMakeSetup) show STATUS messages one at a time on a status
line and other messages in interactive pop-up boxes.
CMake Warning and Error message text displays using a simple
markup language. Non-indented text is formatted in line-wrapped
paragraphs delimited by newlines. Indented text is considered
pre-formatted.
option Provides an option that the user can optionally select.
option(<option_variable> "help string describing option"
[initial value])
Provide an option for the user to select as ON or OFF. If no
initial value is provided, OFF is used.
If you have options that depend on the values of other options,
see the module help for CMakeDependentOption.
project
Set a name for the entire project.
project(<projectname> [languageName1 languageName2 ... ] )
Sets the name of the project. Additionally this sets the vari‐
ables <projectName>_BINARY_DIR and <projectName>_SOURCE_DIR to
the respective values.
Optionally you can specify which languages your project sup‐
ports. Example languages are CXX (i.e. C++), C, Fortran, etc.
By default C and CXX are enabled. E.g. if you do not have a C++
compiler, you can disable the check for it by explicitly listing
the languages you want to support, e.g. C. By using the special
language "NONE" all checks for any language can be disabled. If
a variable exists called CMAKE_PROJECT_<projectName>_INCLUDE,
the file pointed to by that variable will be included as the
last step of the project command.
qt_wrap_cpp
Create Qt Wrappers.
qt_wrap_cpp(resultingLibraryName DestName
SourceLists ...)
Produce moc files for all the .h files listed in the
SourceLists. The moc files will be added to the library using
the DestName source list.
qt_wrap_ui
Create Qt user interfaces Wrappers.
qt_wrap_ui(resultingLibraryName HeadersDestName
SourcesDestName SourceLists ...)
Produce .h and .cxx files for all the .ui files listed in the
SourceLists. The .h files will be added to the library using
the HeadersDestNamesource list. The .cxx files will be added to
the library using the SourcesDestNamesource list.
remove_definitions
Removes -D define flags added by add_definitions.
remove_definitions(-DFOO -DBAR ...)
Removes flags (added by add_definitions) from the compiler com‐
mand line for sources in the current directory and below.
return Return from a file, directory or function.
return()
Returns from a file, directory or function. When this command is
encountered in an included file (via include() or find_pack‐
age()), it causes processing of the current file to stop and
control is returned to the including file. If it is encountered
in a file which is not included by another file, e.g. a CMake‐
Lists.txt, control is returned to the parent directory if there
is one. If return is called in a function, control is returned
to the caller of the function. Note that a macro is not a func‐
tion and does not handle return like a function does.
separate_arguments
Parse space-separated arguments into a semicolon-separated list.
separate_arguments(<var> <UNIX|WINDOWS>_COMMAND "<args>")
Parses a unix- or windows-style command-line string "<args>" and
stores a semicolon-separated list of the arguments in <var>.
The entire command line must be given in one "<args>" argument.
The UNIX_COMMAND mode separates arguments by unquoted white‐
space. It recognizes both single-quote and double-quote pairs.
A backslash escapes the next literal character (\" is "); there
are no special escapes (\n is just n).
The WINDOWS_COMMAND mode parses a windows command-line using the
same syntax the runtime library uses to construct argv at
startup. It separates arguments by whitespace that is not dou‐
ble-quoted. Backslashes are literal unless they precede dou‐
ble-quotes. See the MSDN article "Parsing C Command-Line Argu‐
ments" for details.
separate_arguments(VARIABLE)
Convert the value of VARIABLE to a semi-colon separated list.
All spaces are replaced with ';'. This helps with generating
command lines.
set Set a CMake, cache or environment variable to a given value.
set(<variable> <value>
[[CACHE <type> <docstring> [FORCE]] | PARENT_SCOPE])
Within CMake sets <variable> to the value <value>. <value> is
expanded before <variable> is set to it. Normally, set will set
a regular CMake variable. If CACHE is present, then the <vari‐
able> is put in the cache instead, unless it is already in the
cache. See section 'Variable types in CMake' below for details
of regular and cache variables and their interactions. If CACHE
is used, <type> and <docstring> are required. <type> is used by
the CMake GUI to choose a widget with which the user sets a
value. The value for <type> may be one of
FILEPATH = File chooser dialog.
PATH = Directory chooser dialog.
STRING = Arbitrary string.
BOOL = Boolean ON/OFF checkbox.
INTERNAL = No GUI entry (used for persistent variables).
If <type> is INTERNAL, the cache variable is marked as internal,
and will not be shown to the user in tools like cmake-gui. This
is intended for values that should be persisted in the cache,
but which users should not normally change. INTERNAL implies
FORCE.
Normally, set(...CACHE...) creates cache variables, but does not
modify them. If FORCE is specified, the value of the cache vari‐
able is set, even if the variable is already in the cache. This
should normally be avoided, as it will remove any changes to the
cache variable's value by the user.
If PARENT_SCOPE is present, the variable will be set in the
scope above the current scope. Each new directory or function
creates a new scope. This command will set the value of a vari‐
able into the parent directory or calling function (whichever is
applicable to the case at hand). PARENT_SCOPE cannot be combined
with CACHE.
If <value> is not specified then the variable is removed instead
of set. See also: the unset() command.
set(<variable> <value1> ... <valueN>)
In this case <variable> is set to a semicolon separated list of
values.
<variable> can be an environment variable such as:
set( ENV{PATH} /home/martink )
in which case the environment variable will be set.
*** Variable types in CMake ***
In CMake there are two types of variables: normal variables and
cache variables. Normal variables are meant for the internal use
of the script (just like variables in most programming lan‐
guages); they are not persisted across CMake runs. Cache vari‐
ables (unless set with INTERNAL) are mostly intended for config‐
uration settings where the first CMake run determines a suitable
default value, which the user can then override, by editing the
cache with tools such as ccmake or cmake-gui. Cache variables
are stored in the CMake cache file, and are persisted across
CMake runs.
Both types can exist at the same time with the same name but
different values. When ${FOO} is evaluated, CMake first looks
for a normal variable 'FOO' in scope and uses it if set. If and
only if no normal variable exists then it falls back to the
cache variable 'FOO'.
Some examples:
The code 'set(FOO "x")' sets the normal variable 'FOO'. It does
not touch the cache, but it will hide any existing cache value
'FOO'.
The code 'set(FOO "x" CACHE ...)' checks for 'FOO' in the cache,
ignoring any normal variable of the same name. If 'FOO' is in
the cache then nothing happens to either the normal variable or
the cache variable. If 'FOO' is not in the cache, then it is
added to the cache.
Finally, whenever a cache variable is added or modified by a
command, CMake also *removes* the normal variable of the same
name from the current scope so that an immediately following
evaluation of it will expose the newly cached value.
Normally projects should avoid using normal and cache variables
of the same name, as this interaction can be hard to follow.
However, in some situations it can be useful. One example (used
by some projects):
A project has a subproject in its source tree. The child project
has its own CMakeLists.txt, which is included from the parent
CMakeLists.txt using add_subdirectory(). Now, if the parent and
the child project provide the same option (for example a com‐
piler option), the parent gets the first chance to add a
user-editable option to the cache. Normally, the child would
then use the same value that the parent uses. However, it may be
necessary to hard-code the value for the child project's option
while still allowing the user to edit the value used by the par‐
ent project. The parent project can achieve this simply by set‐
ting a normal variable with the same name as the option in a
scope sufficient to hide the option's cache variable from the
child completely. The parent has already set the cache variable,
so the child's set(...CACHE...) will do nothing, and evaluating
the option variable will use the value from the normal variable,
which hides the cache variable.
set_directory_properties
Set a property of the directory.
set_directory_properties(PROPERTIES prop1 value1 prop2 value2)
Set a property for the current directory and subdirectories. If
the property is not found, CMake will report an error. The prop‐
erties include: INCLUDE_DIRECTORIES, LINK_DIRECTORIES,
INCLUDE_REGULAR_EXPRESSION, and ADDITIONAL_MAKE_CLEAN_FILES.
ADDITIONAL_MAKE_CLEAN_FILES is a list of files that will be
cleaned as a part of "make clean" stage.
set_property
Set a named property in a given scope.
set_property(<GLOBAL |
DIRECTORY [dir] |
TARGET [target1 [target2 ...]] |
SOURCE [src1 [src2 ...]] |
TEST [test1 [test2 ...]] |
CACHE [entry1 [entry2 ...]]>
[APPEND] [APPEND_STRING]
PROPERTY <name> [value1 [value2 ...]])
Set one property on zero or more objects of a scope. The first
argument determines the scope in which the property is set. It
must be one of the following:
GLOBAL scope is unique and does not accept a name.
DIRECTORY scope defaults to the current directory but another
directory (already processed by CMake) may be named by full or
relative path.
TARGET scope may name zero or more existing targets.
SOURCE scope may name zero or more source files. Note that
source file properties are visible only to targets added in the
same directory (CMakeLists.txt).
TEST scope may name zero or more existing tests.
CACHE scope must name zero or more cache existing entries.
The required PROPERTY option is immediately followed by the name
of the property to set. Remaining arguments are used to compose
the property value in the form of a semicolon-separated list.
If the APPEND option is given the list is appended to any exist‐
ing property value.If the APPEND_STRING option is given the
string is append to any existing property value as string, i.e.
it results in a longer string and not a list of strings.
set_source_files_properties
Source files can have properties that affect how they are built.
set_source_files_properties([file1 [file2 [...]]]
PROPERTIES prop1 value1
[prop2 value2 [...]])
Set properties associated with source files using a key/value
paired list. See properties documentation for those known to
CMake. Unrecognized properties are ignored. Source file prop‐
erties are visible only to targets added in the same directory
(CMakeLists.txt).
set_target_properties
Targets can have properties that affect how they are built.
set_target_properties(target1 target2 ...
PROPERTIES prop1 value1
prop2 value2 ...)
Set properties on a target. The syntax for the command is to
list all the files you want to change, and then provide the val‐
ues you want to set next. You can use any prop value pair you
want and extract it later with the GET_TARGET_PROPERTY command.
Properties that affect the name of a target's output file are as
follows. The PREFIX and SUFFIX properties override the default
target name prefix (such as "lib") and suffix (such as ".so").
IMPORT_PREFIX and IMPORT_SUFFIX are the equivalent properties
for the import library corresponding to a DLL (for SHARED
library targets). OUTPUT_NAME sets the real name of a target
when it is built and can be used to help create two targets of
the same name even though CMake requires unique logical target
names. There is also a <CONFIG>_OUTPUT_NAME that can set the
output name on a per-configuration basis. <CONFIG>_POSTFIX sets
a postfix for the real name of the target when it is built under
the configuration named by <CONFIG> (in upper-case, such as
"DEBUG_POSTFIX"). The value of this property is initialized
when the target is created to the value of the variable
CMAKE_<CONFIG>_POSTFIX (except for executable targets because
earlier CMake versions which did not use this variable for exe‐
cutables).
The LINK_FLAGS property can be used to add extra flags to the
link step of a target. LINK_FLAGS_<CONFIG> will add to the con‐
figuration <CONFIG>, for example, DEBUG, RELEASE, MINSIZEREL,
RELWITHDEBINFO. DEFINE_SYMBOL sets the name of the preprocessor
symbol defined when compiling sources in a shared library. If
not set here then it is set to target_EXPORTS by default (with
some substitutions if the target is not a valid C identifier).
This is useful for headers to know whether they are being
included from inside their library or outside to properly setup
dllexport/dllimport decorations. The COMPILE_FLAGS property sets
additional compiler flags used to build sources within the tar‐
get. It may also be used to pass additional preprocessor defi‐
nitions.
The LINKER_LANGUAGE property is used to change the tool used to
link an executable or shared library. The default is set the
language to match the files in the library. CXX and C are common
values for this property.
For shared libraries VERSION and SOVERSION can be used to spec‐
ify the build version and api version respectively. When build‐
ing or installing appropriate symlinks are created if the plat‐
form supports symlinks and the linker supports so-names. If only
one of both is specified the missing is assumed to have the same
version number. For executables VERSION can be used to specify
the build version. When building or installing appropriate sym‐
links are created if the platform supports symlinks. For shared
libraries and executables on Windows the VERSION attribute is
parsed to extract a "major.minor" version number. These numbers
are used as the image version of the binary.
There are a few properties used to specify RPATH rules.
INSTALL_RPATH is a semicolon-separated list specifying the rpath
to use in installed targets (for platforms that support it).
INSTALL_RPATH_USE_LINK_PATH is a boolean that if set to true
will append directories in the linker search path and outside
the project to the INSTALL_RPATH. SKIP_BUILD_RPATH is a boolean
specifying whether to skip automatic generation of an rpath
allowing the target to run from the build tree.
BUILD_WITH_INSTALL_RPATH is a boolean specifying whether to link
the target in the build tree with the INSTALL_RPATH. This takes
precedence over SKIP_BUILD_RPATH and avoids the need for relink‐
ing before installation. INSTALL_NAME_DIR is a string specify‐
ing the directory portion of the "install_name" field of shared
libraries on Mac OSX to use in the installed targets. When the
target is created the values of the variables
CMAKE_INSTALL_RPATH, CMAKE_INSTALL_RPATH_USE_LINK_PATH,
CMAKE_SKIP_BUILD_RPATH, CMAKE_BUILD_WITH_INSTALL_RPATH, and
CMAKE_INSTALL_NAME_DIR are used to initialize these properties.
PROJECT_LABEL can be used to change the name of the target in an
IDE like visual studio. VS_KEYWORD can be set to change the
visual studio keyword, for example QT integration works better
if this is set to Qt4VSv1.0.
VS_SCC_PROJECTNAME, VS_SCC_LOCALPATH, VS_SCC_PROVIDER and
VS_SCC_AUXPATH can be set to add support for source control
bindings in a Visual Studio project file.
VS_GLOBAL_<variable> can be set to add a Visual Studio
project-specific global variable. Qt integration works better if
VS_GLOBAL_QtVersion is set to the Qt version FindQt4.cmake
found. For example, "4.7.3"
The PRE_INSTALL_SCRIPT and POST_INSTALL_SCRIPT properties are
the old way to specify CMake scripts to run before and after
installing a target. They are used only when the old
INSTALL_TARGETS command is used to install the target. Use the
INSTALL command instead.
The EXCLUDE_FROM_DEFAULT_BUILD property is used by the visual
studio generators. If it is set to 1 the target will not be
part of the default build when you select "Build Solution".
set_tests_properties
Set a property of the tests.
set_tests_properties(test1 [test2...] PROPERTIES prop1 value1 prop2 value2)
Set a property for the tests. If the property is not found,
CMake will report an error. The properties include:
WILL_FAIL: If set to true, this will invert the pass/fail flag
of the test.
PASS_REGULAR_EXPRESSION: If set, the test output will be checked
against the specified regular expressions and at least one of
the regular expressions has to match, otherwise the test will
fail.
Example: PASS_REGULAR_EXPRESSION "TestPassed;All ok"
FAIL_REGULAR_EXPRESSION: If set, if the output will match to one
of specified regular expressions, the test will fail.
Example: PASS_REGULAR_EXPRESSION "[^a-z]Error;ERROR;Failed"
Both PASS_REGULAR_EXPRESSION and FAIL_REGULAR_EXPRESSION expect
a list of regular expressions.
TIMEOUT: Setting this will limit the test runtime to the number
of seconds specified.
site_name
Set the given variable to the name of the computer.
site_name(variable)
source_group
Define a grouping for sources in the makefile.
source_group(name [REGULAR_EXPRESSION regex] [FILES src1 src2 ...])
Defines a group into which sources will be placed in project
files. This is mainly used to setup file tabs in Visual Studio.
Any file whose name is listed or matches the regular expression
will be placed in this group. If a file matches multiple
groups, the LAST group that explicitly lists the file will be
favored, if any. If no group explicitly lists the file, the
LAST group whose regular expression matches the file will be
favored.
The name of the group may contain backslashes to specify sub‐
groups:
source_group(outer\\inner ...)
For backwards compatibility, this command is also supports the
format:
source_group(name regex)
string String operations.
string(REGEX MATCH <regular_expression>
<output variable> <input> [<input>...])
string(REGEX MATCHALL <regular_expression>
<output variable> <input> [<input>...])
string(REGEX REPLACE <regular_expression>
<replace_expression> <output variable>
<input> [<input>...])
string(REPLACE <match_string>
<replace_string> <output variable>
<input> [<input>...])
string(<MD5|SHA1|SHA224|SHA256|SHA384|SHA512>
<output variable> <input>)
string(COMPARE EQUAL <string1> <string2> <output variable>)
string(COMPARE NOTEQUAL <string1> <string2> <output variable>)
string(COMPARE LESS <string1> <string2> <output variable>)
string(COMPARE GREATER <string1> <string2> <output variable>)
string(ASCII <number> [<number> ...] <output variable>)
string(CONFIGURE <string1> <output variable>
[@ONLY] [ESCAPE_QUOTES])
string(TOUPPER <string1> <output variable>)
string(TOLOWER <string1> <output variable>)
string(LENGTH <string> <output variable>)
string(SUBSTRING <string> <begin> <length> <output variable>)
string(STRIP <string> <output variable>)
string(RANDOM [LENGTH <length>] [ALPHABET <alphabet>]
[RANDOM_SEED <seed>] <output variable>)
string(FIND <string> <substring> <output variable> [REVERSE])
REGEX MATCH will match the regular expression once and store the
match in the output variable.
REGEX MATCHALL will match the regular expression as many times
as possible and store the matches in the output variable as a
list.
REGEX REPLACE will match the regular expression as many times as
possible and substitute the replacement expression for the match
in the output. The replace expression may refer to paren-delim‐
ited subexpressions of the match using \1, \2, ..., \9. Note
that two backslashes (\\1) are required in CMake code to get a
backslash through argument parsing.
REPLACE will replace all occurrences of match_string in the
input with replace_string and store the result in the output.
MD5, SHA1, SHA224, SHA256, SHA384, and SHA512 will compute a
cryptographic hash of the input string.
COMPARE EQUAL/NOTEQUAL/LESS/GREATER will compare the strings and
store true or false in the output variable.
ASCII will convert all numbers into corresponding ASCII charac‐
ters.
CONFIGURE will transform a string like CONFIGURE_FILE transforms
a file.
TOUPPER/TOLOWER will convert string to upper/lower characters.
LENGTH will return a given string's length.
SUBSTRING will return a substring of a given string. If length
is -1 the remainder of the string starting at begin will be
returned.
STRIP will return a substring of a given string with leading and
trailing spaces removed.
RANDOM will return a random string of given length consisting of
characters from the given alphabet. Default length is 5 charac‐
ters and default alphabet is all numbers and upper and lower
case letters. If an integer RANDOM_SEED is given, its value
will be used to seed the random number generator.
FIND will return the position where the given substring was
found in the supplied string. If the REVERSE flag was used, the
command will search for the position of the last occurrence of
the specified substring.
The following characters have special meaning in regular expres‐
sions:
^ Matches at beginning of a line
$ Matches at end of a line
. Matches any single character
[ ] Matches any character(s) inside the brackets
[^ ] Matches any character(s) not inside the brackets
- Matches any character in range on either side of a dash
* Matches preceding pattern zero or more times
+ Matches preceding pattern one or more times
? Matches preceding pattern zero or once only
| Matches a pattern on either side of the |
() Saves a matched subexpression, which can be referenced
in the REGEX REPLACE operation. Additionally it is saved
by all regular expression-related commands, including
e.g. if( MATCHES ), in the variables CMAKE_MATCH_(0..9).
target_link_libraries
Link a target to given libraries.
target_link_libraries(<target> [item1 [item2 [...]]]
[[debug|optimized|general] <item>] ...)
Specify libraries or flags to use when linking a given target.
The named <target> must have been created in the current direc‐
tory by a command such as add_executable or add_library. The
remaining arguments specify library names or flags. Repeated
calls for the same <target> append items in the order called.
If a library name matches that of another target in the project
a dependency will automatically be added in the build system to
make sure the library being linked is up-to-date before the tar‐
get links. Item names starting with '-', but not '-l' or
'-framework', are treated as linker flags.
A "debug", "optimized", or "general" keyword indicates that the
library immediately following it is to be used only for the cor‐
responding build configuration. The "debug" keyword corresponds
to the Debug configuration (or to configurations named in the
DEBUG_CONFIGURATIONS global property if it is set). The "opti‐
mized" keyword corresponds to all other configurations. The
"general" keyword corresponds to all configurations, and is
purely optional (assumed if omitted). Higher granularity may be
achieved for per-configuration rules by creating and linking to
IMPORTED library targets. See the IMPORTED mode of the
add_library command for more information.
Library dependencies are transitive by default. When this tar‐
get is linked into another target then the libraries linked to
this target will appear on the link line for the other target
too. See the LINK_INTERFACE_LIBRARIES target property to over‐
ride the set of transitive link dependencies for a target.
target_link_libraries(<target> LINK_INTERFACE_LIBRARIES
[[debug|optimized|general] <lib>] ...)
The LINK_INTERFACE_LIBRARIES mode appends the libraries to the
LINK_INTERFACE_LIBRARIES and its per-configuration equivalent
target properties instead of using them for linking. Libraries
specified as "debug" are appended to the the LINK_INTER‐
FACE_LIBRARIES_DEBUG property (or to the properties correspond‐
ing to configurations listed in the DEBUG_CONFIGURATIONS global
property if it is set). Libraries specified as "optimized" are
appended to the the LINK_INTERFACE_LIBRARIES property.
Libraries specified as "general" (or without any keyword) are
treated as if specified for both "debug" and "optimized".
target_link_libraries(<target>
<LINK_PRIVATE|LINK_PUBLIC>
[[debug|optimized|general] <lib>] ...
[<LINK_PRIVATE|LINK_PUBLIC>
[[debug|optimized|general] <lib>] ...])
The LINK_PUBLIC and LINK_PRIVATE modes can be used to specify
both the link dependencies and the link interface in one com‐
mand. Libraries and targets following LINK_PUBLIC are linked
to, and are made part of the LINK_INTERFACE_LIBRARIES. Libraries
and targets following LINK_PRIVATE are linked to, but are not
made part of the LINK_INTERFACE_LIBRARIES.
The library dependency graph is normally acyclic (a DAG), but in
the case of mutually-dependent STATIC libraries CMake allows the
graph to contain cycles (strongly connected components). When
another target links to one of the libraries CMake repeats the
entire connected component. For example, the code
add_library(A STATIC a.c)
add_library(B STATIC b.c)
target_link_libraries(A B)
target_link_libraries(B A)
add_executable(main main.c)
target_link_libraries(main A)
links 'main' to 'A B A B'. (While one repetition is usually
sufficient, pathological object file and symbol arrangements can
require more. One may handle such cases by manually repeating
the component in the last target_link_libraries call. However,
if two archives are really so interdependent they should proba‐
bly be combined into a single archive.)
try_compile
Try building some code.
try_compile(RESULT_VAR <bindir> <srcdir>
<projectName> [targetName] [CMAKE_FLAGS flags...]
[OUTPUT_VARIABLE <var>])
Try building a project. In this form, srcdir should contain a
complete CMake project with a CMakeLists.txt file and all
sources. The bindir and srcdir will not be deleted after this
command is run. Specify targetName to build a specific target
instead of the 'all' or 'ALL_BUILD' target.
try_compile(RESULT_VAR <bindir> <srcfile>
[CMAKE_FLAGS flags...]
[COMPILE_DEFINITIONS flags...]
[OUTPUT_VARIABLE <var>]
[COPY_FILE <fileName>])
Try building a source file into an executable. In this form the
user need only supply a source file that defines a 'main'.
CMake will create a CMakeLists.txt file to build the source as
an executable. Specify COPY_FILE to get a copy of the linked
executable at the given fileName.
In this version all files in bindir/CMakeFiles/CMakeTmp will be
cleaned automatically. For debugging, --debug-trycompile can be
passed to cmake to avoid this clean. However, multiple sequen‐
tial try_compile operations reuse this single output directory.
If you use --debug-trycompile, you can only debug one try_com‐
pile call at a time. The recommended procedure is to configure
with cmake all the way through once, then delete the cache entry
associated with the try_compile call of interest, and then
re-run cmake again with --debug-trycompile.
Some extra flags that can be included are, INCLUDE_DIRECTORIES,
LINK_DIRECTORIES, and LINK_LIBRARIES. COMPILE_DEFINITIONS are
-Ddefinition that will be passed to the compile line. try_com‐
pile creates a CMakeList.txt file on the fly that looks like
this:
add_definitions( <expanded COMPILE_DEFINITIONS from calling cmake>)
include_directories(${INCLUDE_DIRECTORIES})
link_directories(${LINK_DIRECTORIES})
add_executable(cmTryCompileExec sources)
target_link_libraries(cmTryCompileExec ${LINK_LIBRARIES})
In both versions of the command, if OUTPUT_VARIABLE is speci‐
fied, then the output from the build process is stored in the
given variable. The success or failure of the try_compile, i.e.
TRUE or FALSE respectively, is returned in RESULT_VAR.
CMAKE_FLAGS can be used to pass -DVAR:TYPE=VALUE flags to the
cmake that is run during the build. Set variable CMAKE_TRY_COM‐
PILE_CONFIGURATION to choose a build configuration.
try_run
Try compiling and then running some code.
try_run(RUN_RESULT_VAR COMPILE_RESULT_VAR
bindir srcfile [CMAKE_FLAGS <Flags>]
[COMPILE_DEFINITIONS <flags>]
[COMPILE_OUTPUT_VARIABLE comp]
[RUN_OUTPUT_VARIABLE run]
[OUTPUT_VARIABLE var]
[ARGS <arg1> <arg2>...])
Try compiling a srcfile. Return TRUE or FALSE for success or
failure in COMPILE_RESULT_VAR. Then if the compile succeeded,
run the executable and return its exit code in RUN_RESULT_VAR.
If the executable was built, but failed to run, then
RUN_RESULT_VAR will be set to FAILED_TO_RUN. COMPILE_OUT‐
PUT_VARIABLE specifies the variable where the output from the
compile step goes. RUN_OUTPUT_VARIABLE specifies the variable
where the output from the running executable goes.
For compatibility reasons OUTPUT_VARIABLE is still supported,
which gives you the output from the compile and run step com‐
bined.
Cross compiling issues
When cross compiling, the executable compiled in the first step
usually cannot be run on the build host. try_run() checks the
CMAKE_CROSSCOMPILING variable to detect whether CMake is in
crosscompiling mode. If that's the case, it will still try to
compile the executable, but it will not try to run the exe‐
cutable. Instead it will create cache variables which must be
filled by the user or by presetting them in some CMake script
file to the values the executable would have produced if it
would have been run on its actual target platform. These vari‐
ables are RUN_RESULT_VAR (explanation see above) and if RUN_OUT‐
PUT_VARIABLE (or OUTPUT_VARIABLE) was used, an additional cache
variable RUN_RESULT_VAR__COMPILE_RESULT_VAR__TRYRUN_OUTPUT.This
is intended to hold stdout and stderr from the executable.
In order to make cross compiling your project easier, use
try_run only if really required. If you use try_run, use
RUN_OUTPUT_VARIABLE (or OUTPUT_VARIABLE) only if really
required. Using them will require that when crosscompiling, the
cache variables will have to be set manually to the output of
the executable. You can also "guard" the calls to try_run with
if(CMAKE_CROSSCOMPILING) and provide an easy-to-preset alterna‐
tive for this case.
Set variable CMAKE_TRY_COMPILE_CONFIGURATION to choose a build
configuration.
unset Unset a variable, cache variable, or environment variable.
unset(<variable> [CACHE])
Removes the specified variable causing it to become undefined.
If CACHE is present then the variable is removed from the cache
instead of the current scope.
<variable> can be an environment variable such as:
unset(ENV{LD_LIBRARY_PATH})
in which case the variable will be removed from the current
environment.
variable_watch
Watch the CMake variable for change.
variable_watch(<variable name> [<command to execute>])
If the specified variable changes, the message will be printed
about the variable being changed. If the command is specified,
the command will be executed. The command will receive the fol‐
lowing arguments: COMMAND(<variable> <access> <value> <current
list file> <stack>)
while Evaluate a group of commands while a condition is true
while(condition)
COMMAND1(ARGS ...)
COMMAND2(ARGS ...)
...
endwhile(condition)
All commands between while and the matching endwhile are
recorded without being invoked. Once the endwhile is evaluated,
the recorded list of commands is invoked as long as the condi‐
tion is true. The condition is evaluated using the same logic as
the if command.
COPYRIGHT
Copyright 2000-2009 Kitware, Inc., Insight Software Consortium. All
rights reserved.
Redistribution and use in source and binary forms, with or without mod‐
ification, are permitted provided that the following conditions are
met:
Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
Neither the names of Kitware, Inc., the Insight Software Consortium,
nor the names of their contributors may be used to endorse or promote
products derived from this software without specific prior written per‐
mission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTIC‐
ULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
SEE ALSO
The following resources are available to get help using CMake:
Home Page
http://www.cmake.org
The primary starting point for learning about CMake.
Frequently Asked Questions
http://www.cmake.org/Wiki/CMake_FAQ
A Wiki is provided containing answers to frequently asked ques‐
tions.
Online Documentation
http://www.cmake.org/HTML/Documentation.html
Links to available documentation may be found on this web page.
Mailing List
http://www.cmake.org/HTML/MailingLists.html
For help and discussion about using cmake, a mailing list is
provided at cmake@cmake.org. The list is member-post-only but
one may sign up on the CMake web page. Please first read the
full documentation at http://www.cmake.org before posting ques‐
tions to the list.
Summary of helpful links:
Home: http://www.cmake.org
Docs: http://www.cmake.org/HTML/Documentation.html
Mail: http://www.cmake.org/HTML/MailingLists.html
FAQ: http://www.cmake.org/Wiki/CMake_FAQ
cmake 2.8.9 October 02, 2012 cmakecommands(1)
