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
The following environment variables shall affect the execution of ulimit:
Provide a default value for the internationalization
variables that are unset or null. (See the Base Definitions volume of
IEEE Std 1003.1-2001, Section 8.2, Internationalization
Variables for the precedence of internationalization variables used to
determine the values of locale categories.)
If set to a non-empty string value, override the values of
all the other internationalization variables.
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).
Determine the locale that should be used to affect the
format and contents of diagnostic messages written to standard error.
Determine the location of message catalogs for the
processing of LC_MESSAGES.
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 10000env 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.
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html