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PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT |
C99(1P) POSIX Programmer's Manual C99(1P)
This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior), or
the interface may not be implemented on Linux.
c99 — compile standard C programs
c99 [options...] pathname [[pathname] [−I directory]
[−L directory] [−l library]]...
The c99 utility is an interface to the standard C compilation system;
it shall accept source code conforming to the ISO C standard. The
system conceptually consists of a compiler and link editor. The input
files referenced by pathname operands and −l option-arguments shall
be compiled and linked to produce an executable file. (It is
unspecified whether the linking occurs entirely within the operation
of c99; some implementations may produce objects that are not fully
resolved until the file is executed.)
If the −c option is specified, for all pathname operands of the form
file.c, the files:
$(basename pathname .c).o
shall be created as the result of successful compilation. If the −c
option is not specified, it is unspecified whether such .o files are
created or deleted for the file.c operands.
If there are no options that prevent link editing (such as −c or −E),
and all input files compile and link without error, the resulting
executable file shall be written according to the −o outfile option
(if present) or to the file a.out.
The executable file shall be created as specified in Section 1.1.1.4,
File Read, Write, and Creation, except that the file permission bits
shall be set to: S_IRWXO | S_IRWXG | S_IRWXU
and the bits specified by the umask of the process shall be cleared.
The c99 utility shall conform to the Base Definitions volume of
POSIX.1‐2008, Section 12.2, Utility Syntax Guidelines, except that:
* Options can be interspersed with operands.
* The order of specifying the −L and −l options, and the order of
specifying −l options with respect to pathname operands is
significant.
* Conforming applications shall specify each option separately;
that is, grouping option letters (for example, −cO) need not be
recognized by all implementations.
The following options shall be 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 shall 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 shall be
undefined regardless of the order of the options.
Additional implementation-defined names may be provided by
the compiler. Implementations shall support at least 2048
bytes of −D definitions and 256 names.
−E Copy C-language source files to standard output, expanding
all preprocessor directives; no compilation shall be
performed. If any operand is not a text file, the effects
are unspecified.
−g Produce symbolic information in the object or executable
files; the nature of this information is unspecified, and
may be modified by implementation-defined interactions with
other options.
−I directory
Change the algorithm for searching for headers whose names
are not absolute pathnames to look in the directory named
by the directory pathname before looking in the usual
places. Thus, headers whose names are enclosed in double-
quotes ("") shall 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 shall be searched for only in directories named in
−I options and then in the usual places. Directories named
in −I options shall be searched in the order specified. If
the −I option is used to specify a directory that is one of
the usual places searched by default, the results are
unspecified. Implementations shall support at least ten
instances of this option in a single c99 command
invocation.
−L directory
Change the algorithm of searching for the libraries named
in the −l objects to look in the directory named by the
directory pathname before looking in the usual places.
Directories named in −L options shall be searched in the
order specified. If the −L option is used to specify a
directory that is one of the usual places searched by
default, the results are unspecified. Implementations shall
support at least ten instances of this option in a single
c99 command invocation. If a directory specified by a −L
option contains files with names starting with any of the
strings "libc.", "libl.", "libpthread.", "libm.", "librt.",
"libtrace.", "libxnet.", or "liby.", the results are
unspecified.
−l library
Search the library named liblibrary.a. A library shall be
searched when its name is encountered, so the placement of
a −l option is significant. Several standard libraries can
be specified in this manner, as described in the EXTENDED
DESCRIPTION section. Implementations may recognize
implementation-defined suffixes other than .a as denoting
libraries.
−O optlevel
Specify the level of code optimization. If the optlevel
option-argument is the digit '0', all special code
optimizations shall be disabled. If it is the digit '1',
the nature of the optimization is unspecified. If the −O
option is omitted, the nature of the system's default
optimization is unspecified. It is unspecified whether code
generated in the presence of the −O 0 option is the same as
that generated when −O is omitted. Other optlevel values
may be supported.
−o outfile
Use the pathname outfile, instead of the default a.out, for
the executable file produced. If the −o option is present
with −c or −E, the result is unspecified.
−s Produce object or executable files, or both, from which
symbolic and other information not required for proper
execution using the exec family defined in the System
Interfaces volume of POSIX.1‐2008 has been removed
(stripped). If both −g and −s options are present, the
action taken is unspecified.
−U name Remove any initial definition of name.
Multiple instances of the −D, −I, −L, −l, and −U options can be
specified.
The application shall ensure that at least one pathname operand is
specified. The following forms for pathname operands shall be
supported:
file.c A C-language source file to be compiled and optionally
linked. The application shall ensure that the operand is of
this form if the −c option is used.
file.a A library of object files typically produced by the ar
utility, and passed directly to the link editor.
Implementations may recognize implementation-defined
suffixes other than .a as denoting object file libraries.
file.o An object file produced by c99 −c and passed directly to
the link editor. Implementations may recognize
implementation-defined suffixes other than .o as denoting
object files.
The processing of other files is implementation-defined.
Not used.
Each input file shall be one of the following: a text file containing
a C-language source program, an object file in the format produced by
c99 −c, or a library of object files, in the format produced by
archiving zero or more object files, using ar. Implementations may
supply additional utilities that produce files in these formats.
Additional input file formats are implementation-defined.
The following environment variables shall affect the execution of
c99:
LANG Provide a default value for the internationalization
variables that are unset or null. (See the Base Definitions
volume of POSIX.1‐2008, Section 8.2, Internationalization
Variables for the precedence of internationalization
variables used to determine the values of locale
categories.)
LC_ALL If set to a non-empty string value, override the values of
all the other internationalization variables.
LC_CTYPE Determine the locale for the interpretation of sequences of
bytes of text data as characters (for example, single-byte
as opposed to multi-byte characters in arguments and input
files).
LC_MESSAGES
Determine the locale that should be used to affect the
format and contents of diagnostic messages written to
standard error.
NLSPATH Determine the location of message catalogs for the
processing of LC_MESSAGES.
TMPDIR Provide a pathname that should override the default
directory for temporary files, if any. On XSI-conforming
systems, provide a pathname that shall override the default
directory for temporary files, if any.
Default.
If more than one pathname operand ending in .c (or possibly other
unspecified suffixes) is given, for each such file:
"%s:\n", <pathname>
may be written. These messages, if written, shall precede the
processing of each input file; they shall not be written to the
standard output if they are written to the standard error, as
described in the STDERR section.
If the −E option is specified, the standard output shall 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.
The standard error shall be used only for diagnostic messages. If
more than one pathname operand ending in .c (or possibly other
unspecified suffixes) is given, for each such file:
"%s:\n", <pathname>
may be written to allow identification of the diagnostic and warning
messages with the appropriate input file. These messages, if written,
shall precede the processing of each input file; they shall not be
written to the standard error if they are written to the standard
output, as described in the STDOUT section.
This utility may produce warning messages about certain conditions
that do not warrant returning an error (non-zero) exit value.
Object files or executable files or both are produced in unspecified
formats. If the pathname of an object file or executable file to be
created by c99 resolves to an existing directory entry for a file
that is not a regular file, it is unspecified whether c99 shall
attempt to create the file or shall issue a diagnostic and exit with
a non-zero exit status.
Standard Libraries
The c99 utility shall recognize the following −l options for standard
libraries:
−l c This option shall make available all interfaces referenced
in the System Interfaces volume of POSIX.1‐2008, with the
possible exception of those interfaces listed as residing
in <aio.h>, <arpa/inet.h>, <complex.h>, <fenv.h>, <math.h>,
<mqueue.h>, <netdb.h>, <net/if.h>, <netinet/in.h>,
<pthread.h>, <sched.h>, <semaphore.h>, <spawn.h>,
<sys/socket.h>, pthread_kill(), and pthread_sigmask() in
<signal.h>, <trace.h>, interfaces marked as optional in
<sys/mman.h>, interfaces marked as ADV (Advisory
Information) in <fcntl.h>, and interfaces beginning with
the prefix clock_ or time_ in <time.h>. This option shall
not be required to be present to cause a search of this
library.
−l l This option shall make available all interfaces required by
the C-language output of lex that are not made available
through the −l c option.
−l pthread
This option shall make available all interfaces referenced
in <pthread.h> and pthread_kill() and pthread_sigmask()
referenced in <signal.h>. An implementation may search
this library in the absence of this option.
−l m This option shall make available all interfaces referenced
in <math.h>, <complex.h>, and <fenv.h>. An implementation
may search this library in the absence of this option.
−l rt This option shall make available all interfaces referenced
in <aio.h>, <mqueue.h>, <sched.h>, <semaphore.h>, and
<spawn.h>, interfaces marked as optional in <sys/mman.h>,
interfaces marked as ADV (Advisory Information) in
<fcntl.h>, and interfaces beginning with the prefix clock_
and time_ in <time.h>. An implementation may search this
library in the absence of this option.
−l trace This option shall make available all interfaces referenced
in <trace.h>. An implementation may search this library in
the absence of this option.
−l xnet This option shall make available all interfaces referenced
in <arpa/inet.h>, <netdb.h>, <net/if.h>, <netinet/in.h>,
and <sys/socket.h>. An implementation may search this
library in the absence of this option.
−l y This option shall make available all interfaces required by
the C-language output of yacc that are not made available
through the −l c option.
In the absence of options that inhibit invocation of the link editor,
such as −c or −E, the c99 utility shall cause the equivalent of a
−l c option to be passed to the link editor after the last pathname
operand or −l option, causing it to be searched after all other
object files and libraries are loaded.
It is unspecified whether the libraries libc.a, libl.a, libm.a,
libpthread.a, librt.a, libtrace.a, libxnet.a, or liby.a exist as
regular files. The implementation may accept as −l option-arguments
names of objects that do not exist as regular files.
External Symbols
The C compiler and link editor shall support the significance of
external symbols up to a length of at least 31 bytes; the action
taken upon encountering symbols exceeding the implementation-defined
maximum symbol length is unspecified.
The compiler and link editor shall support a minimum of 511 external
symbols per source or object file, and a minimum of 4095 external
symbols in total. A diagnostic message shall be written to the
standard output if the implementation-defined limit is exceeded;
other actions are unspecified.
Header Search
If a file with the same name as one of the standard headers defined
in the Base Definitions volume of POSIX.1‐2008, Chapter 13, Headers,
not provided as part of the implementation, is placed in any of the
usual places that are searched by default for headers, the results
are unspecified.
Programming Environments
All implementations shall support one of the following programming
environments as a default. Implementations may support more than one
of the following programming environments. Applications can use
sysconf() or getconf to determine which programming environments are
supported.
Table 4-4: Programming Environments: Type Sizes
┌────────────────────────┬─────────┬─────────┬─────────┬─────────┐
│Programming Environment │ Bits in │ Bits in │ Bits in │ Bits in │
│ getconf Name │ int │ long │ pointer │ off_t │
├────────────────────────┼─────────┼─────────┼─────────┼─────────┤
│_POSIX_V7_ILP32_OFF32 │ 32 │ 32 │ 32 │ 32 │
│_POSIX_V7_ILP32_OFFBIG │ 32 │ 32 │ 32 │ ≥64 │
│_POSIX_V7_LP64_OFF64 │ 32 │ 64 │ 64 │ 64 │
│_POSIX_V7_LPBIG_OFFBIG │ ≥32 │ ≥64 │ ≥64 │ ≥64 │
└────────────────────────┴─────────┴─────────┴─────────┴─────────┘
All implementations shall support one or more environments where the
widths of the following types are no greater than the width of type
long:
blksize_t ptrdiff_t tcflag_t
cc_t size_t wchar_t
mode_t speed_t wint_t
nfds_t ssize_t
pid_t suseconds_t
The executable files created when these environments are selected
shall be in a proper format for execution by the exec family of
functions. Each environment may be one of the ones in Table 4-4,
Programming Environments: Type Sizes, or it may be another
environment. The names for the environments that meet this
requirement shall be output by a getconf command using the
POSIX_V7_WIDTH_RESTRICTED_ENVS argument, as a <newline>-separated
list of names suitable for use with the getconf −v option. If more
than one environment meets the requirement, the names of all such
environments shall be output on separate lines. Any of these names
can then be used in a subsequent getconf command to obtain the flags
specific to that environment with the following suffixes added as
appropriate:
_CFLAGS To get the C compiler flags.
_LDFLAGS To get the linker/loader flags.
_LIBS To get the libraries.
This requirement may be removed in a future version.
When this utility processes a file containing a function called
main(), it shall be defined with a return type equivalent to int.
Using return from the initial call to main() shall be equivalent
(other than with respect to language scope issues) to calling exit()
with the returned value. Reaching the end of the initial call to
main() shall be equivalent to calling exit(0). The implementation
shall not declare a prototype for this function.
Implementations provide configuration strings for C compiler flags,
linker/loader flags, and libraries for each supported environment.
When an application needs to use a specific programming environment
rather than the implementation default programming environment while
compiling, the application shall first verify that the implementation
supports the desired environment. If the desired programming
environment is supported, the application shall then invoke c99 with
the appropriate C compiler flags as the first options for the
compile, the appropriate linker/loader flags after any other options
except −l but before any operands or −l options, and the appropriate
libraries at the end of the operands and −l options.
Conforming applications shall not attempt to link together object
files compiled for different programming models. Applications shall
also be aware that binary data placed in shared memory or in files
might not be recognized by applications built for other programming
models.
Table 4-5: Programming Environments: c99 Arguments
┌────────────────────────┬─────────────────────┬───────────────────────────────┐
│Programming Environment │ │ c99 Arguments │
│ getconf Name │ Use │ getconf Name │
├────────────────────────┼─────────────────────┼───────────────────────────────┤
│_POSIX_V7_ILP32_OFF32 │ C Compiler Flags │ POSIX_V7_ILP32_OFF32_CFLAGS │
│ │ Linker/Loader Flags │ POSIX_V7_ILP32_OFF32_LDFLAGS │
│ │ Libraries │ POSIX_V7_ILP32_OFF32_LIBS │
├────────────────────────┼─────────────────────┼───────────────────────────────┤
│_POSIX_V7_ILP32_OFFBIG │ C Compiler Flags │ POSIX_V7_ILP32_OFFBIG_CFLAGS │
│ │ Linker/Loader Flags │ POSIX_V7_ILP32_OFFBIG_LDFLAGS │
│ │ Libraries │ POSIX_V7_ILP32_OFFBIG_LIBS │
├────────────────────────┼─────────────────────┼───────────────────────────────┤
│_POSIX_V7_LP64_OFF64 │ C Compiler Flags │ POSIX_V7_LP64_OFF64_CFLAGS │
│ │ Linker/Loader Flags │ POSIX_V7_LP64_OFF64_LDFLAGS │
│ │ Libraries │ POSIX_V7_LP64_OFF64_LIBS │
├────────────────────────┼─────────────────────┼───────────────────────────────┤
│_POSIX_V7_LPBIG_OFFBIG │ C Compiler Flags │ POSIX_V7_LPBIG_OFFBIG_CFLAGS │
│ │ Linker/Loader Flags │ POSIX_V7_LPBIG_OFFBIG_LDFLAGS │
│ │ Libraries │ POSIX_V7_LPBIG_OFFBIG_LIBS │
└────────────────────────┴─────────────────────┴───────────────────────────────┘
In addition to the type size programming environments above, all
implementations also support a multi-threaded programming environment
that is orthogonal to all of the programming environments listed
above. The getconf utility can be used to get flags for the threaded
programming environment, as indicated in Table 4-6, Threaded
Programming Environment: c99 Arguments.
Table 4-6: Threaded Programming Environment: c99 Arguments
┌────────────────────────┬─────────────────────┬──────────────────────────┐
│Programming Environment │ │ c99 Arguments │
│ getconf Name │ Use │ getconf Name │
├────────────────────────┼─────────────────────┼──────────────────────────┤
│_POSIX_THREADS │ C Compiler Flags │ POSIX_V7_THREADS_CFLAGS │
│ │ Linker/Loader Flags │ POSIX_V7_THREADS_LDFLAGS │
└────────────────────────┴─────────────────────┴──────────────────────────┘
These programming environment flags may be used in conjunction with
any of the type size programming environments supported by the
implementation.
The following exit values shall be 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 shall write a diagnostic to standard error and
continue to compile other source code operands, but it shall not
perform the link phase and return a non-zero exit status. If the link
edit is unsuccessful, a diagnostic message shall be written to
standard error and c99 exits with a non-zero status. A conforming
application shall rely on the exit status of c99, rather than on the
existence or mode of the executable file.
The following sections are informative.
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.
On systems providing POSIX Conformance (see the Base Definitions
volume of POSIX.1‐2008, Chapter 2, Conformance), c99 is required only
with the C-Language Development option; XSI-conformant systems always
provide c99.
Some historical implementations have created .o files when −c is not
specified and more than one source file is given. Since this area is
left unspecified, the application cannot rely on .o files being
created, but it also must be prepared for any related .o files that
already exist being deleted at the completion of the link edit.
There is the possible implication that if a user supplies versions of
the standard 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 on), so the existence of files named in the same
manner as the standard libraries within the −L directories is
explicitly stated to produce unspecified behavior.
All of the functions specified in the System Interfaces volume of
POSIX.1‐2008 may be made visible by implementations when the Standard
C Library is searched. Conforming applications must explicitly
request searching the other standard libraries when functions made
visible by those libraries are used.
In the ISO C standard the mapping from physical source characters to
the C source character set is implementation-defined. Implementations
may strip white-space characters before the terminating <newline> of
a (physical) line as part of this mapping and, as a consequence of
this, one or more white-space characters (and no other characters)
between a <backslash> character and the <newline> character that
terminates the line produces implementation-defined results. Portable
applications should not use such constructs.
Some c99 compilers not conforming to POSIX.1‐2008 do not support
trigraphs by default.
1. The following usage example compiles foo.c and creates the
executable file foo:
c99 −o foo foo.c
The following usage example compiles foo.c and creates the object
file foo.o:
c99 −c foo.c
The following usage example compiles foo.c and creates the
executable file a.out:
c99 foo.c
The following usage example compiles foo.c, links it with bar.o,
and creates the executable file a.out. It may also create and
leave foo.o:
c99 foo.c bar.o
2. The following example shows how an application using threads
interfaces can test for support of and use a programming
environment supporting 32-bit int, long, and pointer types and an
off_t type using at least 64 bits:
offbig_env=$(getconf _POSIX_V7_ILP32_OFFBIG)
if [ $offbig_env != "-1" ] && [ $offbig_env != "undefined" ]
then
c99 $(getconf POSIX_V7_ILP32_OFFBIG_CFLAGS) \
$(getconf POSIX_V7_THREADS_CFLAGS) -D_XOPEN_SOURCE=700 \
$(getconf POSIX_V7_ILP32_OFFBIG_LDFLAGS) \
$(getconf POSIX_V7_THREADS_LDFLAGS) foo.c -o foo \
$(getconf POSIX_V7_ILP32_OFFBIG_LIBS) \
-l pthread
else
echo ILP32_OFFBIG programming environment not supported
exit 1
fi
3. The following examples clarify the use and interactions of −L and
−l options.
Consider the case in which module a.c calls function f() in
library libQ.a, and module b.c calls function g() in library
libp.a. Assume that both libraries reside in /a/b/c. The
command line to compile and link in the desired way is:
c99 −L /a/b/c main.o a.c −l Q b.c −l p
In this case the −L option need only precede the first −l option,
since both libQ.a and libp.a reside in the same directory.
Multiple −L options can be used when library name collisions
occur. Building on the previous example, suppose that the user
wants to use a new libp.a, in /a/a/a, but still wants f() from
/a/b/c/libQ.a:
c99 −L /a/a/a −L /a/b/c main.o a.c −l Q b.c −l p
In this example, the linker searches the −L options in the order
specified, and finds /a/a/a/libp.a before /a/b/c/libp.a when
resolving references for b.c. The order of the −l options is
still important, however.
4. The following example shows how an application can use a
programming environment where the widths of the following types:
blksize_t, cc_t, mode_t, nfds_t, pid_t, ptrdiff_t, size_t,
speed_t, ssize_t, suseconds_t, tcflag_t, wchar_t, wint_t
are no greater than the width of type long:
# First choose one of the listed environments ...
# ... if there are no additional constraints, the first one will do:
CENV=$(getconf POSIX_V7_WIDTH_RESTRICTED_ENVS | head -n l)
# ... or, if an environment that supports large files is preferred,
# look for names that contain "OFF64" or "OFFBIG". (This chooses
# the last one in the list if none match.)
for CENV in $(getconf POSIX_V7_WIDTH_RESTRICTED_ENVS)
do
case $CENV in
*OFF64*|*OFFBIG*) break ;;
esac
done
# The chosen environment name can now be used like this:
c99 $(getconf ${CENV}_CFLAGS) -D _POSIX_C_SOURCE=200809L \
$(getconf ${CENV}_LDFLAGS) foo.c -o foo \
$(getconf ${CENV}_LIBS)
The c99 utility is based on the c89 utility originally introduced in
the ISO POSIX‐2:1993 standard.
Some of the changes from c89 include the ability to intersperse
options and operands (which many c89 implementations allowed despite
it not being specified), the description of −l as an option instead
of an operand, and the modification to the contents of the Standard
Libraries section to account for new headers and options; for
example, <spawn.h> added to the description of −l rt, and −l trace
added for the Tracing option.
POSIX.1‐2008 specifies that the c99 utility must be able to use
regular files for *.o files and for a.out files. Implementations are
free to overwrite existing files of other types when attempting to
create object files and executable files, but are not required to do
so. If something other than a regular file is specified and using it
fails for any reason, c99 is required to issue a diagnostic message
and exit with a non-zero exit status. But for some file types, the
problem may not be noticed for a long time. For example, if a FIFO
named a.out exists in the current directory, c99 may attempt to open
a.out and will hang in the open() call until another process opens
the FIFO for reading. Then c99 may write most of the a.out to the
FIFO and fail when it tries to seek back close to the start of the
file to insert a timestamp (FIFOs are not seekable files). The c99
utility is also allowed to issue a diagnostic immediately if it
encounters an a.out or *.o file that is not a regular file. For
portable use, applications should ensure that any a.out, −o option-
argument, or *.o files corresponding to any *.c files do not conflict
with names already in use that are not regular files or symbolic
links that point to regular files.
On many systems, multi-threaded applications run in a programming
environment that is distinct from that used by single-threaded
applications. This multi-threaded programming environment (in
addition to needing to specify −l pthread at link time) may require
additional flags to be set when headers are processed at compile time
(−D_REENTRANT being common). This programming environment is
orthogonal to the type size programming environments discussed above
and listed in Table 4-4, Programming Environments: Type Sizes. This
version of the standard adds getconf utility calls to provide the C
compiler flags and linker/loader flags needed to support multi-
threaded applications. Note that on a system where single-threaded
applications are a special case of a multi-threaded application, both
of these getconf calls may return NULL strings; on other
implementations both of these strings may be non-NULL strings.
The C standardization committee invented trigraphs (e.g., "??!" to
represent '|') to address character portability problems in
development environments based on national variants of the 7-bit
ISO/IEC 646:1991 standard character set. However, these environments
were already obsolete by the time the first ISO C standard was
published, and in practice trigraphs have not been used for their
intended purpose, and usually are intended to have their original
meaning in K&R C. For example, in practice a C-language source
string like "What??!" is usually intended to end in two <question-
mark> characters and an <exclamation-mark>, not in '|'.
None.
Section 1.1.1.4, File Read, Write, and Creation, ar(1p), getconf(1p),
make(1p), nm(1p), strip(1p), umask(1p)
The Base Definitions volume of POSIX.1‐2008, Chapter 8, Environment
Variables, Section 12.2, Utility Syntax Guidelines, Chapter 13,
Headers
The System Interfaces volume of POSIX.1‐2008, exec(1p), sysconf(3p)
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 7, Copyright (C) 2013 by the
Institute of Electrical and Electronics Engineers, Inc and The Open
Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
applied.) In the event of any discrepancy between this version and
the original IEEE and The Open Group Standard, the original IEEE and
The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the
source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 C99(1P)
Pages that refer to this page: ar(1p), cflow(1p), ctags(1p), cxref(1p), fort77(1p), getconf(1p), lex(1p), m4(1p), make(1p), nm(1p), od(1p), strip(1p), yacc(1p), confstr(3p)