sysconf


>>-sysconf--name-----------------------------------------------><

Function

sysconf invokes the sysconf callable service to get the value of a configurable system variable.

Parameters

name

A numeric value that specifies the configurable variable to be returned. You can specify a numeric value (seeREXX predefined variables) or the predefined variable beginning with SC_ used to derive the appropriate numeric value:

Variable	Description
SC_ARG_MAX	The maximum length of all arguments and environment strings to exec()
SC_CHILD_MAX	The maximum number of simultaneous processes per real user ID
SC_CLK_TCK	The number of intervals per second used in defining the type clock_t, which is used to measure process execution times
SC_JOB_CONTROL	Support for job control
SC_NGROUPS_MAX	Maximum number of simultaneous supplementary group IDs per process
SC_OPEN_MAX	Maximum number of simultaneous open files per process
SC_SAVED_IDS	Support for saved set-user-IDs and set-group-IDs
SC_THREAD_TASKS_MAX_NP	Constant for querying the maximum number of threaded tasks per calling process
SC_THREADS_MAX_NP	Constant for querying the maximum number of threads per calling process
SC_TZNAME_MAX	The number of bytes supported for the name of a time zone
SC_VERSION	The integer value 199009L
SC_2_CHAR_TERM	Constant for querying whether the system supports at least one raw mode terminal

Usage notes

SC_MAX_THREADS_NP and SC_MAX_THREAD_TASKS_NP return the limits defined for the caller's process, not the systemwide limits.

Example

To determine the maximum number of files that a single process can have open at one time:

"sysconf" sc_open_max
maxopenfiles = retval    /*value of desired configurable system 
                           variable is returned in retval*/