The
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
In 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
St -p1003.1-2001
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:
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
Vt long .
At present, all programming environments supported by
Fx have this property.
Several of the
confstr(3)
variables provide information on the necessary compiler and linker flags
to use the standard programming environments described above.
EXIT STATUS
Ex -std
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
Vt long
in the
POSIX_V6_LPBIG_OFFBIG
programming environment,
if the system supports that environment.
DIAGNOSTICS
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
utility recognizes all of the variables defined for
St -p1003.1-2001 ,
including those which are not currently implemented.
