.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved .TH "ULIMIT" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" .\" ulimit .SH NAME ulimit \- set or report file size limit .SH SYNOPSIS .LP \fBulimit\fP \fB[\fP\fB-f\fP\fB][\fP\fIblocks\fP\fB]\fP\fB\fP .SH DESCRIPTION .LP The \fIulimit\fP 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. .SH OPTIONS .LP The \fIulimit\fP utility shall conform to the Base Definitions volume of IEEE\ Std\ 1003.1-2001, Section 12.2, Utility Syntax Guidelines. .LP The following option shall be supported: .TP 7 \fB-f\fP Set (or report, if no \fIblocks\fP operand is present), the file size limit in blocks. The \fB-f\fP option shall also be the default case. .sp .SH OPERANDS .LP The following operand shall be supported: .TP 7 \fIblocks\fP The number of 512-byte blocks to use as the new file size limit. .sp .SH STDIN .LP Not used. .SH INPUT FILES .LP None. .SH ENVIRONMENT VARIABLES .LP The following environment variables shall affect the execution of \fIulimit\fP: .TP 7 \fILANG\fP 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.) .TP 7 \fILC_ALL\fP If set to a non-empty string value, override the values of all the other internationalization variables. .TP 7 \fILC_CTYPE\fP 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). .TP 7 \fILC_MESSAGES\fP Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error. .TP 7 \fINLSPATH\fP Determine the location of message catalogs for the processing of \fILC_MESSAGES \&.\fP .sp .SH ASYNCHRONOUS EVENTS .LP Default. .SH STDOUT .LP The standard output shall be used when no \fIblocks\fP 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: .sp .RS .nf \fB"%d\\n", <\fP\fInumber of 512-byte blocks\fP\fB> \fP .fi .RE .LP If there is no current limit on the number of blocks, in the POSIX locale the following format shall be used: .sp .RS .nf \fB"unlimited\\n" \fP .fi .RE .SH STDERR .LP The standard error shall be used only for diagnostic messages. .SH OUTPUT FILES .LP None. .SH EXTENDED DESCRIPTION .LP None. .SH EXIT STATUS .LP The following exit values shall be returned: .TP 7 \ 0 Successful completion. .TP 7 >0 A request for a higher limit was rejected or an error occurred. .sp .SH CONSEQUENCES OF ERRORS .LP Default. .LP \fIThe following sections are informative.\fP .SH APPLICATION USAGE .LP Since \fIulimit\fP 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: .sp .RS .nf \fBnohup ulimit -f 10000 env ulimit 10000 \fP .fi .RE .LP it does not affect the file size limit of the caller's environment. .LP 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. .SH EXAMPLES .LP Set the file size limit to 51200 bytes: .sp .RS .nf \fBulimit -f 100 \fP .fi .RE .SH RATIONALE .LP None. .SH FUTURE DIRECTIONS .LP None. .SH SEE ALSO .LP The System Interfaces volume of IEEE\ Std\ 1003.1-2001, \fIulimit\fP() .SH COPYRIGHT 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 .