PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT 

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

PROLOG         top

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

NAME         top

       ulimit — set or report file size limit

SYNOPSIS         top

       ulimit [−f] [blocks]

DESCRIPTION         top

       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         top

       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         top

       The following operand shall be supported:
       blocks    The number of 512-byte blocks to use as the new file size
                 limit.

STDIN         top

       Not used.

INPUT FILES         top

       None.

ENVIRONMENT VARIABLES         top

       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         top

       Default.

STDOUT         top

       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\n", <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\n"

STDERR         top

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES         top

       None.

EXTENDED DESCRIPTION         top

       None.

EXIT STATUS         top

       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         top

       Default.
       The following sections are informative.

APPLICATION USAGE         top

       Since ulimit affects the current shell execution environment, it is
       always provided as a shell regular built-in. If it is called in a
       separate 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
       original system limit.

EXAMPLES         top

       Set the file size limit to 51200 bytes:
           ulimit −f 100

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       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(3p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information
       Technology -- 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 Standard 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)