# PXFSYSCONF

POSIX Subroutine: Gets values for system limits or options.

## Module

USE IFPOSIX

CALL PXFSYSCONF (name,ival,ierror)

name | (Input) INTEGER(4). The system option you want information about.
ival | (Output) INTEGER(4). The returned value.
ierror | (Output) INTEGER(4). The error status.

If successful, ierror is set to zero; otherwise, an error code.

PXFSYSCONF lets you determine values for system limits or system options at runtime.

The value for name can be any of the following constants:

Constant | Description
--- | ---
_SC_ARG_MAX1 | Indicates the maximum length of the arguments to the PXFEXEC family of routines.
_SC_CHILD_MAX1 | Indicates the number of simultaneous processes per user ID.
_SC_CLK_TCK | Indicates the number of clock ticks per second.
_SC_STREAM_MAX2 | Indicates the maximum number of streams that a process can have open at any time.
_SC_TZNAME_MAX | Indicates the maximum number of bytes in a timezone name.
_SC_OPEN_MAX | Indicates the maximum number of files that a process can have open at any time.
_SC_JOB_CONTROL1 | Indicates whether POSIX-style job control is supported.
_SC_SAVED_IDS1 | Indicates whether a process has a saved set-user-ID and a saved set-group-ID.
_SC_VERSION1 | Indicates the year and month the POSIX.1 standard was approved in the format YYYYMML; the value 199009L indicates the most recent revision, 1990.
_SC_BC_BASE_MAX1 | Indicates the maximum obase value accepted by the bc(1) utility.
_SC_BC_DIM_MAX1 | Indicates the maximum value of elements that bc(1) permits in an array.
_SC_BC_SCALE_MAX1 | Indicates the maximum scale value allowed by bc(1).
_SC_BC_STRING_MAX1 | Indicates the maximum length of a string accepted by bc(1).
_SC_COLL_WEIGHTS_MAX1 | Indicates the maximum numbers of weights that can be assigned to an entry of the LC_COLLATE order keyword in the locale definition file.
_SC_EXPR_NEST_MAX1,3 | Indicates the maximum number of expressions that can be nested within parentheses by expr(1).
_SC_LINE_MAX1 | Indicates the maximum length of a utility's input line length, either from standard input or from a file. This includes the length for a trailing newline.
_SC_RE_DUP_MAX1 | Indicates the maximum number of repeated occurrences of a regular expression when the interval notation \{m,n\} is used.
_SC_2_VERSION1 | Indicates the version of the POSIX.2 standard; it is in the format YYYYMML.
_SC_2_DEV1 | Indicates whether the POSIX.2 C language development facilities are supported.
_SC_2_FORT_DEV1 | Indicates whether the POSIX.2 FORTRAN language development utilities are supported.
_SC_2_FORT_RUN1 | Indicates whether the POSIX.2 FORTRAN runtime utilities are supported.
_SC_2_LOCALEDEF1 | Indicates whether the POSIX.2 creation of locates via localedef(1) is supported.
_SC_2_SW_DEV1 | Indicates whether the POSIX.2 software development utilities option is supported.
_SC_PAGESIZE (or _SC_PAGE_SIZE) | Indicates the size of a page (in bytes).
_SC_PHYS_PAGES4 | Indicates the number of pages of physical memory. Note that it is possible for the product of this value and the value of _SC_PAGE_SIZE to overflow.
_SC_AVPHYS_PAGES4 | Indicates the number of currently available pages of physical memory.
1L*X only 2The corresponding POSIX macro is STREAM_MAX. 3The corresponding POSIX macro is EXPR_NEST_MAX. 4L*X, W*32

The corresponding macros are defined in <bits/confname.h> on Linux* systems; <unistd.h> on macOS systems. The values for argument name can be obtained by using PXFCONST or IPXFCONST when passing the string names of predefined macros in the appropriate .h file.

Parent topic: POSIX* Library Routines

## See Also

IPXFCONST
PXFCONST