GETCONF(1) BSD General Commands Manual GETCONF(1)
NAME
getconf -- retrieve standard configuration variables
SYNOPSIS
getconf [-v environment] path_var file
getconf [-v environment] system_var
DESCRIPTION
The getconf utility prints the value of a POSIX or X/Open path or system configuration variable to the
standard output. If the specified variable is undefined, the string ``undefined'' is output.
The first form of the command, with two mandatory arguments, retrieves file- and file system-specific
configuration variables using pathconf(2). The second form, with a single argument, retrieves system
configuration variables using confstr(3) and sysconf(3), depending on the type of variable. As an
extension, the second form can also be used to query static limits from <limits.h>.
All sysconf(3) and pathconf(2) variables use the same name as the manifest constants defined in the
relevant standard C-language bindings, including any leading underscore or prefix. That is to say,
system_var might be ARG_MAX or _POSIX_VERSION, as opposed to the sysconf(3) names _SC_ARG_MAX or
_SC_POSIX_VERSION. Variables retrieved from confstr(3) have the leading `_CS_' stripped off; thus,
_CS_PATH is queried by a system_var of ``PATH''.
Programming Environments
The -v environment option specifies a IEEE Std 1003.1-2001 (``POSIX.1'') programming environment under
which the values are to be queried. This option currently does nothing, but may in the future be used
to select between 32-bit and 64-bit execution environments on platforms which support both. Specifying
an environment which is not supported on the current execution platform gives undefined results.
The standard programming environments are as follows:
POSIX_V6_ILP32_OFF32 Exactly 32-bit integer, long, pointer, and file offset. Supported
platforms: None.
POSIX_V6_ILP32_OFFBIG Exactly 32-bit integer, long, and pointer; at least 64-bit file offset.
Supported platforms: IA32, PowerPC.
POSIX_V6_LP64_OFF64 Exactly 32-bit integer; exactly 64-bit long, pointer, and file offset.
Supported platforms: Alpha, SPARC64.
POSIX_V6_LPBIG_OFFBIG At least 32-bit integer; at least 64-bit long, pointer, and file offset.
Supported platforms: None.
The command:
getconf POSIX_V6_WIDTH_RESTRICTED_ENVS
returns a newline-separated list of environments in which the width of certain fundamental types is no
greater than the width of the native C type long. At present, all programming environments supported
by FreeBSD have this property. Several of the confstr(3) variables provide information on the neces-sary necessary
sary compiler and linker flags to use the standard programming environments described above.
Many of these values are also available through the sysctl(8) mechanism.
DIAGNOSTICS
The getconf utility exits 0 on success, and >0 if an error occurs. Use of a system_var or path_var
which is completely unrecognized is considered an error, causing a diagnostic message to be written to
standard error. One which is known but merely undefined does not result in an error indication. The
getconf utility recognizes all of the variables defined for IEEE Std 1003.1-2001 (``POSIX.1''), includ-ing including
ing those which are not currently implemented.
EXAMPLES
The command:
getconf PATH
will display the system default setting for the PATH environment variable.
The command:
getconf NAME_MAX /tmp
will display the maximum length of a filename in the /tmp directory.
The command:
getconf -v POSIX_V6_LPBIG_OFFBIG LONG_MAX
will display the maximum value of the C type long in the POSIX_V6_LPBIG_OFFBIG programming environment,
if the system supports that environment.
SEE ALSO
pathconf(2), confstr(3), sysconf(3), sysctl(8)
STANDARDS
The getconf utility is expected to be compliant with IEEE Std 1003.1-2001 (``POSIX.1'').
HISTORY
The getconf utility first appeared in FreeBSD 5.0.
AUTHORS
Garrett A. Wollman <wollman@lcs.mit.edu>
BSD September 18, 2002 BSD
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