POSIX Subroutine: Gets values for system limits or options.
Module: USE IFPOSIX
Syntax
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. | |
| 1 L*X only 2 The corresponding POSIX macro is STREAM_MAX. 3 The corresponding POSIX macro is EXPR_NEST_MAX. 4 L*X, W*32, W*64 |
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The corresponding macros are defined in <bits/confname.h> on Linux* systems; <unistd.h> on Mac OS* 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.
See Also