c99(1)c99(1)NAMEc99 - compile standard C programs
SYNOPSISc99 [-c] [-Dname[=tokens]] [-E] [-g] [-Idirectory] [-Ldirectory]
[-Ooptlevel] [-ooutfile] [-s] [-Uname]
DESCRIPTION
This release of the c99 utility is compliant with the
Standard for Information Technology - Portable Operating System Inter‐
face (POSIX(R))
Shell and Utilities, Issue 6 (Volume 1: A to J) Approved 12 September
2001.
The c99 utility is an interface to the standard C compilation system;
it will accept source code conforming to the ISO C standard. The sys‐
tem conceptually consists of a compiler and link editor. The files
referenced by operands will be compiled and linked to produce an exe‐
cutable file.
If the -c option is specified, for all pathname operands of the form
file.c,the files:
$(basename pathname .c).o
will be created as the result of successful compilation.
If there are no options that prevent link editing (such as -c or -E),
and all operands compile and link without error, the resulting exe‐
cutable file will be written according to the -o outfile option (if
present) or to the file a.out.
The file permissions for the executable file that is created are set to
S_IRWXO | S_IRWXG | S_IRWXU
and the bits specified by the umask of the process are cleared.
OPTIONS
The following affect the options for the c99 utility:
· The -l library operands have the format of options, but their
position within a list of operands affects the order in which
libraries are searched.
· The order of specifying the -I and -L options is significant.
· Portable applications must specify each option separately; that
is, grouping option letters (for example, -cO) need not be rec‐
ognized by all implementations.
The following options are supported:
-c Suppress the link-edit phase of the compilation, and do
not remove any object files that are produced.
-D name[=value]
Define name as if by a C-language #define directive. If
no =value is given, a value of 1 will be used. The -D
option has lower precedence than the -U option; that is,
if name is used in both a -U and a -D option, name will
be undefined regardless of the order of the options.
c99 supports at least 2048 bytes of -D definitions and
256 names.
The following predefined names are valid in all modes:
__sparc (SPARC)
__i386 (x86)
__unix
__sun
__BUILTIN_VA_ARG_INCR
__SUNPRO_C=0x570
__SVR4
The following names are not predefined:
unix
sparc (SPARC)
i386 (x86)
sun
-E Copy C-language source files to standard output, expand‐
ing all preprocessor directives; no compilation will be
performed. An error will occur if any operand is not a
text file.
-g Produce symbolic information in the object or executable
files.
-I directory Change the algorithm for searching for headers whose
names are not absolute pathnames to look in the direc‐
tory named by the directory path name before looking in
the usual places. Thus, headers whose names are
enclosed in double-quotes ("") will be searched for
first in the directory of the file with the #include
line, then in directories named in -I options, and last
in the usual places. For headers whose names are
enclosed in angle brackets (<>), the header will be
searched for only in directories named in -I options and
then in the usual places. Directories named in -I
options will be searched in the order specified.
-L directory Change the algorithm of searching for the libraries
named in the -l objects to look in the directory named
by the directory path name before looking in the usual
places. Directories named in -L options will be
searched in the order specified.
-O optlevel Specify the level of code optimization. If the optlevel
option-argument is the digit 0, all special code opti‐
mizations are disabled. See the cc(1) manpage for a
description of the optimization levels.
-o outfile Use the pathname outfile, instead of the default a.out,
for the executable file produced. This option cannot be
used with -c or -E.
-s Produce object or executable files, or both, from which
symbolic and other information not required for proper
execution using the exec family has been removed
(stripped). If both -g and -s options are present, -s
overrides -g.
-U name Remove any initial definition of name.
Multiple instances of the -D, -I, -U, and -L options can be specified.
OPERANDS
An operand is either in the form of a path name or the form -l library.
At least one operand of the path name form must be specified. The fol‐
lowing operands are supported:
file.c A C-language source file to be compiled and optionally
linked. The operand must be of this form if the -c
option is used.
file.a A library of object files typically produced by the
ar(1) utility, and passed directly to the link editor.
file.o An object file produced by c99-c and passed directly to
the link editor.
-l library (The letter ell.) Search the library named:
liblibrary.a
A library will be searched when its name is encountered,
so the placement of a -l operand is significant. Sev‐
eral standard libraries can be specified in this manner.
See Standard Libraries in NOTES below.
USAGE
Since the c99 utility usually creates files in the current directory
during the compilation process, it is typically necessary to run the
c99 utility in a directory in which a file can be created.
c99 creates .o files when -c is not specified and more than one source
file is given.
Some historical implementations have permitted -L options to be inter‐
spersed with -l operands on the command line. For an application to
compile consistently on systems that do not behave like this, it is
necessary for a portable application to supply all -L options before
any of the -l options.
There is the possible implication that if a user supplies versions of
the standard library functions (before they would be encountered by an
implicit -l c or explicit -l m), that those versions would be used in
place of the standard versions. There are various reasons this might
not be true (functions defined as macros, manipulations for clean name
space, and so forth), so the existence of files named in the same man‐
ner as the standard libraries within the -L directories is explicitly
stated to produce unspecified behavior.
Setting the environment variable TMPDIR overrides the default temporary
directory.
OUTPUT
STDOUT
If more than one file operand ending in .c is given, for each such
file:
"%s:\n", <file>
may be written. These messages, if written, will precede the process‐
ing of each input file; they will not be written to the standard output
if they are written to the standard error, as described in STDERR.
If the -E option is specified, the standard output will be a text file
that represents the results of the preprocessing stage of the language;
it may contain extra information appropriate for subsequent compilation
passes.
STDERR
Used only for diagnostic messages. If more than one file operand end‐
ing in .c (or possibly other unspecified suffixes) is given, for each
such file:
"%s:\n", <file>
may be written to allow identification of the diagnostic and warning
messages with the appropriate input file. These messages, if written,
will precede the processing of each input file; they will not be writ‐
ten to the standard error if they are written to the standard output,
as described in STDOUT.
ENVIRONMENT
See environ(5) for descriptions of the following environment variables
that affect the execution of c99: LANG, LC_ALL, LC_TYPE, LC_MESSAGES,
and NLSPATH.
TMPDIR Provide a path name that will override the default
directory for temporary files, if any.
EXIT STATUS
The following exit values are returned:
0 Successful compilation or link edit.
>0 An error occurred.
When c99 encounters a compilation error that causes an object file not
to be created, it will write a diagnostic to standard error and con‐
tinue to compile other source code operands, but it will not perform
the link phase and will return a non-zero exit status. If the link
edit is unsuccessful, a diagnostic message will be written to standard
error and c99 will exit with a non-zero status. A portable application
must rely on the exit status of c99, rather than on the existence or
mode of the executable file.
EXAMPLES
The following are examples of usage:
c99-o foo foo.c Compiles foo.c and creates the executable file
foo.
c99-c foo.c Compiles foo.c and creates the object file
foo.o.
c99 foo.c Compiles foo.c and creates the executable file
a.out.
c99 foo.c bar.o Compiles foo.c, links it with bar.o, and cre‐
ates the executable file a.out. Also creates
and leaves foo.o.
The following examples clarify the use and interactions of -L options
and -l operands: Consider the case in which module a.c calls function f
in library libQ.a, and module b.c calls function g in library libp.a.
Assume that both libraries reside in /a/b/c. The command line to com‐
pile and link in the desired way is:
c99-L /a/b/c main.o a.c -l Q b.c -l p
In this case the -l Q operand need only precede the first
-l p operand, since both libQ.a and libp.a reside in the same direc‐
tory.
Multiple -L operands can be used when library name collisions occur.
Building on the previous example, suppose that the user wants to use a
new libp.a, in /a/a/a, but still wants f from /a/b/c/libQ.a:
c99-L /a/a/a -L /a/b/c main.o a.c -l Q b.c -l p
In this example, the linker searches the -L options in the order speci‐
fied, and finds /a/a/a/libp.a before /a/b/c/libp.a when resolving ref‐
erences for b.c. The order of the -l operands is still important, how‐
ever.
SEE ALSOar(1), cc(1B), nm(1), strip(1), umask(1), environ(5)NOTES
Standard Libraries
The c99 utility recognizes the following -l operands for standard
libraries:
-l c This library contains all library functions except for
those functions listed as residing in <math.h>. This oper‐
and is not required to be present to cause a search of this
library.
-l m This library contains all functions referenced in math.h.
An implementation may search this library in the absence of
this operand.
-l l This library contains all functions required by the C-lan‐
guage output of lex that are not made available through the
-l c operand.
-l pthread This operand makes visible all functions referenced in
<pthread.h> and pthread_atfork() referenced in <unistd.h>.
An implementation may search this library in the absence of
this operand.
-l rt This operand makes visible all functions referenced in
<aio.h>, <mqueue.h>, <sched.h>, and <time.h>. An implemen‐
tation may search this library in the absence of this oper‐
and.
-l y This library contains all functions required by the C-lan‐
guage output of yacc that are not made available through
the -l c operand.
In the absence of options that inhibit invocation of the link editor,
such as -c or -E, the c99 utility will cause the equivalent of a -l c
operand to be passed to the link editor as the last -l operand, causing
it to be searched after all other object files and libraries are
loaded.
External Symbols
The C compiler and link editor support the significance of external
symbols up to a length of at least 31 bytes.
The compiler and link editor support a minimum of 511 external symbols
per source or object file, and a minimum of 4095 external symbols in
total. A diagnostic message will be written to the standard output if
the limit is exceeded.
2004/07/30 Release c99(1)
