sysconf(3C)          COMPATIBILITY FUNCTIONS          sysconf(3C)



NAME
     sysconf - get configurable system variables

SYNOPSIS
     #include <unistd.h>

     long sysconf(int name);

DESCRIPTION
     The sysconf function provides a method for  the  application
     to  determine  the  current  value  of a configurable system
     limit or option (variable).  The  name  argument  represents
     the  system  variable  to  be  queried.  The following table
     lists the minimal set of system  variables  from  <limits.h>
     and <unistd.h> that can be returned by sysconf, and the sym-
     bolic  constants,  defined  in  <unistd.h>  that   are   the
     corresponding_values_used_for_name._______________
              |                                       |
              |       NAME             RETURN VALUE   |
              |_______________________________________|
              | _SC_ARG_MAX         ARG_MAX           |
              | _SC_CHILD_MAX       CHILD_MAX         |
              | _SC_CLK_TCK         CLK_TCK           |
              | _SC_NGROUPS_MAX     NGROUPS_MAX       |
              | _SC_OPEN_MAX        OPEN_MAX          |
              | _SC_PASS_MAX        PASS_MAX          |
              | _SC_PAGESIZE        PAGESIZE          |
              | _SC_JOB_CONTROL     _POSIX_JOB_CONTROL|
              | _SC_SAVED_IDS       _POSIX_SAVED_IDS  |
              | _SC_VERSION         _POSIX_VERSION    |
              | _SC_XOPEN_VERSION   _XOPEN_VERSION    |
              | _SC_LOGNAME_MAX     LOGNAME_MAX       |
              |_______________________________________|
     The value of CLKTCK may be variable and it  should  not  be
     assumed  that CLKTCK is a compile-time constant.  The value
     of CLKTCK is the same as the value of sysconf(SCCLKTCK).

SEE ALSO
     fpathconf(3C).

DIAGNOSTICS
     If name is an invalid value, sysconf will return -1 and  set
     errno  to  indicate  the  error.   If sysconf fails due to a
     value of name that is not defined on the system,  the  func-
     tion will return a value of -1 without changing the value of
     errno.

NOTES
     A call to setrlimit may  cause  the  value  of  OPENMAX  to
     change.





          Last change: C Programming Language Utilities         1