SYSCONF(3)                      Domain/OS BSD                       SYSCONF(3)



NAME
     sysconf - Get configurable system variables

SYNOPSIS
     #include <unistd.h>

     long sysconf (name)
     int name;

DESCRIPTION
     The sysconf function provides a method for determining the current value
     of a configurable system limit or whether optional features are
     supported.

     The name argument specifies the system variable to be queried.

     The following list specifies the system variables from the limits.h or
     unistd.h include file that are returned by sysconf, and the symbolic
     constants, defined in the unistd.h header file that correspond to the
     name argument:

                      ______________________________________
                      |Variable             Value of name   |
                      |                                     |
                      |ARG_MAX              _SC_ARG_MAX     |
                      |CHILD_MAX            _SC_CHILD_MAX   |
                      |clock ticks/second   _SC_CLK_TCK     |
                      |NGROUPS_MAX          _SC_NGROUPS_MAX |
                      |OPEN_MAX             _SC_OPEN_MAX    |
                      |_POSIX_JOB_CONTROL   _SC_JOB_CONTROL |
                      |_POSIX_SAVED_IDS     _SC_SAVED_IDS   |
                      |_POSIX_VERSION       _SC_VERSION     |
                      |STREAM_MAX           _SC_STREAM_MAX  |
                      _TZNAME_MAX____________SC_TZNAME_MAX__|


     For these variables described in <limits.h>, the value returned by
     sysconf is equal to or greater than the corresponding Minimum Acceptable
     Value specified in  <limits.h>.

NOTES
     The sysconf system call, when interrogating _SC_NGROUPS_MAX, will always
     return 8 at sr10.4.  (In prior releases, it returned 9 in a Domain/OS BSD
     environment.)

DIAGNOSTICS
     If the name argument is an invalid value, sysconf returns -1 and sets
     errno to indicate the error.  If the variable corresponding to name is
     undefined, sysconf returns -1 without changing the value of errno.

     Otherwise, sysconf returns the current variable value. The value returned
     will not be more restrictive than the corresponding value at the time the
     application is compiled. The value will not change during the lifetime of
     the calling process.

     Note that if name is _SC_JOB_CONTROL or _SC_SAVED_IDS, sysconf returns a
     nonnegative value.

ERRORS
     sysconf fails if:

     [EINVAL]       The value of the name argument is invalid.

SEE ALSO
     pathconf(3) <limits.h> <unistd.h> <time.h>