imake(1X)imake(1X)NAMEimake - C preprocessor interface to the make utility
SYNOPSISimake [-Ddefine] [-Idir] [-Ttemplate] [-f filename] [-C filename] [-s
filename] [-e] [-v]
OPTIONS
The following command line options may be passed to imake: This option
is passed directly to cpp. It is typically used to set directory-spe‐
cific variables. For example, the X Window System uses this option to
set TOPDIR to the name of the directory containing the top of the core
distribution and CURDIR to the name of the current directory, relative
to the top. This option is passed directly to cpp. It is typically
used to indicate the directory in which the imake template and configu‐
ration files may be found. This option specifies the name of the mas‐
ter template file (which is usually located in the directory specified
with -I) used by cpp. The default is Imake.tmpl. This option specifies
the name of the per-directory input file. The default is Imakefile.
This option specifies the name of the file that is constructed in the
current directory. The default is Imakefile.c. This option specifies
the name of the make description file to be generated but make should
not be invoked. If the filename is a dash (-), the output is written to
stdout. The default is to generate, but not execute, a Makefile. This
option indicates the imake should execute the generated Makefile. The
default is to leave this to the user. This option indicates that imake
should print the cpp command line that it is using to generate the
Makefile.
DESCRIPTION
Imake is used to generate Makefiles from a template, a set of cpp macro
functions, and a per-directory input file called an Imakefile. This
allows machine dependencies (such as compiler options, alternate com‐
mand names, and special make rules) to be kept separate from the
descriptions of the various items to be built.
HOW IT WORKS
Imake invokes cpp with any -I or -D options passed on the command line
and passes the name of a file containing the following 3 lines:
#define IMAKE_TEMPLATE "Imake.tmpl" #define INCLUDE_IMAKEFILE <Imake‐
file> #include IMAKE_TEMPLATE
where Imake.tmpl and Imakefile may be overridden by the -T and -f com‐
mand options, respectively.
The IMAKE_TEMPLATE typically reads in a file containing machine-depen‐
dent parameters (specified as cpp symbols), a site-specific parameters
file, a file defining variables, a file containing cpp macro functions
for generating make rules, and finally the Imakefile (specified by
INCLUDE_IMAKEFILE) in the current directory. The Imakefile uses the
macro functions to indicate what targets should be built; imake takes
care of generating the appropriate rules.
Imake configuration files contain two types of variables, imake vari‐
ables and make variables. The imake variables are interpreted by cpp
when imake is run. By convention they are mixed case. The make vari‐
ables are written into the Makefile for later interpretation by make.
By convention make variables are upper case.
The rules file (usually named Imake.rules in the configuration direc‐
tory) contains a variety of cpp macro functions that are configured
according to the current platform. Imake replaces any occurrences of
the string “@@” with a newline to allow macros that generate more than
one line of make rules. For example, the macro
#define program_target(program, objlist) @@\ program: objlist
@@\
$(CC) -o $@ objlist $(LDFLAGS)
when called with
program_target(foo, foo1.o foo2.o)
will expand to
foo: foo1.o foo2.o
$(CC) -o $@ foo1.o foo2.o $(LDFLAGS)
Imake also replaces any occurrences of the word “XCOMM” with the char‐
acter “#” to permit placing comments in the Makefile without causing
“invalid directive” errors from the preprocessor.
Some complex imake macros require generated make variables local to
each invocation of the macro, often because their value depends on
parameters passed to the macro. Such variables can be created by using
an imake variable of the form XVARdefn, where n is a single digit. A
unique make variable will be substituted. Later occurrences of the
variable XVARusen will be replaced by the variable created by the cor‐
responding XVARdefn.
On systems whose cpp reduces multiple tabs and spaces to a single
space, imake attempts to put back any necessary tabs (make is very
picky about the difference between tabs and spaces). For this reason,
colons (:) in command lines must be preceded by a backslash (\).
USE WITH THE X WINDOW SYSTEM
The X Window System uses imake extensively, for both full builds within
the source tree and external software. As mentioned above, two special
variables, TOPDIR and CURDIR, are set to make referencing files using
relative path names easier. For example, the following command is gen‐
erated automatically to build the Makefile in the directory lib/X/
(relative to the top of the sources):
% ../.././config/imake -I../.././config \
-DTOPDIR=../../. -DCURDIR=./lib/X
When building X programs outside the source tree, a special symbol Use‐
Installed is defined and TOPDIR and CURDIR are omitted. If the config‐
uration files have been properly installed, the xmkmf script may be
used.
INPUT FILES
Here is a summary of the files read by imake as used by X. The inden‐
tation shows what files include what other files.
Imake.tmpl generic variables
site.def site-specific, BeforeVendorCF defined
*.cf machine-specific
*Lib.rules shared library rules
site.def site-specific, AfterVendorCF defined
Imake.rules rules
Project.tmpl X-specific variables
*Lib.tmpl shared library variables
Imakefile
Library.tmpl library rules
Server.tmpl server rules
Threads.tmpl multi-threaded rules
Note that site.def gets included twice, once before the *.cf file and
once after. Although most site customizations should be specified
after the *.cf file, some, such as the choice of compiler, need to be
specified before, because other variable settings may depend on them.
The first time site.def is included, the variable BeforeVendorCF is
defined, and the second time, the variable AfterVendorCF is defined.
All code in site.def should be inside an #ifdef for one of these sym‐
bols.
ENVIRONMENT VARIABLES
The following environment variables may be set, however their use is
not recommended as they introduce dependencies that are not readily
apparent when imake is run: If defined, this should be a valid include
argument for the C preprocessor. E.g., “-I/usr/include/local”. Actu‐
ally, any valid cpp argument will work here. If defined, this should
be a valid path to a preprocessor program. E.g., “/usr/local/cpp”. By
default, imake will use /lib/cpp. If defined, this should be a valid
path to a make program, such as “/usr/local/make”. By default, imake
will use whatever make program is found using execvp(2). This variable
is only used if the “-e” option is specified.
FILES
Temporary input file for cpp Temporary Makefile for -s" Temporary
Imakefile if specified Imakefile uses # comments Default C preprocessor
SEE ALSOmake(1), xmkmf(1X)
S. I. Feldman, Make -- A Program for Maintaining Computer Programs
AUTHOR
Todd Brunhoff, Tektronix and MIT Project Athena; Jim Fulton, MIT X Con‐
sortium
imake(1X)
