posix man page for ulimit

ULIMIT(1P)						     POSIX Programmer's Manual							ULIMIT(1P)

PROLOG
       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME
       ulimit -- set or report file size limit

SYNOPSIS
       ulimit [-f] [blocks]

DESCRIPTION
       The ulimit utility shall set or report the file-size writing limit imposed on files written by the shell and its child processes (files	of
       any size may be read). Only a process with appropriate privileges can increase the limit.

OPTIONS
       The ulimit utility shall conform to the Base Definitions volume of POSIX.1-2008, Section 12.2, Utility Syntax Guidelines.

       The following option shall be supported:

       -f	 Set (or report, if no blocks operand is present), the file size limit in blocks. The -f option shall also be the default case.

OPERANDS
       The following operand shall be supported:

       blocks	 The number of 512-byte blocks to use as the new file size limit.

STDIN
       Not used.

INPUT FILES
       None.

ENVIRONMENT VARIABLES
       The following environment variables shall affect the execution of ulimit:

       LANG	 Provide  a  default  value  for  the  internationalization  variables that are unset or null. (See the Base Definitions volume of
		 POSIX.1-2008, Section 8.2, Internationalization Variables for the precedence of internationalization variables used to  determine
		 the values of locale categories.)

       LC_ALL	 If set to a non-empty string value, override the values of all the other internationalization variables.

       LC_CTYPE  Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed
		 to multi-byte characters in arguments).

       LC_MESSAGES
		 Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error.

       NLSPATH	 Determine the location of message catalogs for the processing of LC_MESSAGES.

ASYNCHRONOUS EVENTS
       Default.

STDOUT
       The standard output shall be used when no blocks operand is present. If the current number of blocks is limited, the number  of	blocks	in
       the current limit shall be written in the following format:

	   "%d
", <number of 512-byte blocks>

       If there is no current limit on the number of blocks, in the POSIX locale the following format shall be used:

	   "unlimited
"

STDERR
       The standard error shall be used only for diagnostic messages.

OUTPUT FILES
       None.

EXTENDED DESCRIPTION
       None.

EXIT STATUS
       The following exit values shall be returned:

	0    Successful completion.

       >0    A request for a higher limit was rejected or an error occurred.

CONSEQUENCES OF ERRORS
       Default.

       The following sections are informative.

APPLICATION USAGE
       Since ulimit affects the current shell execution environment, it is always provided as a shell regular built-in. If it is called in a sepa-
       rate utility execution environment, such as one of the following:

	   nohup ulimit -f 10000
	   env ulimit 10000

       it does not affect the file size limit of the caller's environment.

       Once a limit has been decreased by a process, it cannot be increased (unless appropriate privileges are involved), even back to the  origi-
       nal system limit.

EXAMPLES
       Set the file size limit to 51200 bytes:

	   ulimit -f 100

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       The Base Definitions volume of POSIX.1-2008, Chapter 8, Environment Variables, Section 12.2, Utility Syntax Guidelines

       The System Interfaces volume of POSIX.1-2008, ulimit()

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C)  2013  by	the  Institute	of
       Electrical and Electronics Engineers, Inc and The Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
       event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Stan-
       dard is the referee document. The original Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE
/The Open Group						       2013								ULIMIT(1P)