getconf

Get system configuration values (POSIX)

Syntax:

getconf system_var
getconf path_var pathname

Options:

None.

Description:

This utility gets system configuration values, including:

  • configuration strings, whose names start with _CS_
  • configurable system limits, whose names start with _SC_
  • configurable limits associated with a path, whose names start with _PC_

The names of these variables are in uppercase, but getconf and setconf let you use any case, omit the leading underscore, or the entire prefix — provided that the rest of the name is unambiguous.

The first form writes to standard output the value of the specified system variable. The possible values of system_var are those for sysconf() and confstr() (see the C Library Reference):

_CS_ARCHITECTURE
The name of the instruction set architecture for this node's CPU(s).
_CS_DOMAIN
The domain name.
_CS_HOSTNAME
The name of this node in the network.

A hostname can consist only of letters, numbers, and hyphens, and must not start or end with a hyphen. For more information, see RFC 952.

_CS_HW_PROVIDER
The name of the hardware manufacturer.
_CS_HW_SERIAL
Serial number associated with the hardware.
_CS_LIBPATH
A value similar to the LD_LIBRARY_PATH environment variable that finds all standard libraries.
_CS_LOCALE
The name of the current locale.
_CS_MACHINE
This node's hardware type.
_CS_PATH
A value similar to the PATH environment variable that finds all standard utilities.
_CS_RELEASE
The current OS release level.
_CS_RESOLVE
The contents of the resolv.conf file, excluding the domain name.
_CS_SRPC_DOMAIN
The secure RPC domain.
_CS_SYSNAME
The name of the operating system.
_CS_TIMEZONE
Time zone string (TZ style)
_CS_VERSION
The current OS version number.
_SC_AIO_PRIO_DELTA_MAX
The maximum amount by which a process can decrease its asynchronous I/O priority level from its own scheduling priority.
_SC_ARG_MAX
Maximum length of arguments for the exec*() functions, in bytes, including environment data.
_SC_CHILD_MAX
Maximum number of simultaneous processes per real user ID.
_SC_CLK_TCK
The number of intervals per second used to express the value in type clock_t.
_SC_DELAYTIMER_MAX
The maximum number of times a timer can overrun and you can still detect it.
_SC_GETGR_R_SIZE_MAX
If defined (not -1), the maximum size of buffer that you need to supply to getgrgid_r() for any memory that it needs to allocate.
_SC_GETPW_R_SIZE_MAX
If defined (not -1), the maximum size of buffer that you need to supply to getpwent_r(), getpwuid_r(), getspent_r(), or getspnam_r() for any memory that they need to allocate.
_SC_JOB_CONTROL
If this variable is defined, then job control is supported.
_SC_NGROUPS_MAX
The maximum number of simultaneous supplementary group IDs per process.
_SC_OPEN_MAX
Maximum number of files that one process can have open at any given time.
_SC_PAGESIZE
The default size of a thread's guard area.
_SC_SAVED_IDS
If this variable is defined, then each process has a saved set-user ID and a saved set-group ID.
_SC_SEM_NSEMS_MAX
The maximum number of semaphores that one process can have open at a time. The getconf utility reports a value of -1 to indicate that this limit is indeterminate because it applies to both named and unnamed semaphores. The kernel allows an arbitrary number of unnamed semaphores (they're kernel synchronization objects, so the number of them is limited only by the amount of available kernel memory).
_SC_SIGQUEUE_MAX
The maximum number of outstanding realtime signals sent per process.
_SC_THREAD_STACK_MIN
The minimum stack size for a thread.
_SC_TZNAME_MAX
The maximum length of the names for time zones.
_SC_VERSION
The current POSIX version that is currently supported. A value of 198808L indicates the August (08) 1988 standard, as approved by the IEEE Standards Board.

The second form writes to standard output the value of the specified path variable for the given path. The possible values of path_var are those for pathconf() (see the C Library Reference):

_PC_ASYNC_IO
Defined if asynchronous I/O is supported for the file.
_PC_CHOWN_RESTRICTED
If defined (not -1), indicates that the use of the chown function is restricted to a process with root privileges, and to changing the group ID of a file to the effective group ID of the process or to one of its supplementary group IDs.
_PC_LINK_DIR
Defined (not -1) if the filesystem permits the unlinking of a directory.
_PC_LINK_MAX
Maximum value of a file's link count.
_PC_MAX_CANON
Maximum number of bytes in a terminal's canonical input buffer (edit buffer).
_PC_MAX_INPUT
Maximum number of bytes in a terminal's raw input buffer.
_PC_NAME_MAX
Maximum number of bytes in a file name (not including the terminating null).
_PC_NO_TRUNC
If defined (not -1), indicates that the use of pathname components longer than the value given by _PC_NAME_MAX will generate an error.
_PC_PATH_MAX
Maximum number of bytes in a pathname (not including the terminating null).
_PC_PIPE_BUF
Maximum number of bytes that can be written atomically when writing to a pipe.
_PC_PRIO_IO
Defined (not -1) if prioritized I/O is supported for the file.
_PC_SYNC_IO
Defined (not -1) if synchronous I/O is supported for the file.
_PC_VDISABLE
If defined (not -1), this is the character value which can be used to individually disable special control characters in the termios control structure.

Examples:

$ getconf _CS_PATH
/bin
$ getconf _SC_ARG_MAX
61440
$ getconf _PC_LINK_MAX /bin
65535

Environment variables:

LANG
The locale to use for the locale categories.

BlackBerry 10 OS currently supports only the POSIX (i.e. C) locale.

Exit status:

0
Successful completion.
1
An error occurred.

Last modified: 2014-06-24



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