xref: /titanic_51/usr/src/man/man2/ulimit.2 (revision 356f72340a69936724c69f2f87fffa6f5887f885)
te
Copyright 1989 AT&T. Copyright (c) 2003, Sun Microsystems, Inc. All Rights Reserved. Portions Copyright (c) 1992, X/Open Company Limited All Rights Reserved
Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.
The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions 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.
This notice shall appear on any product containing this material.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
ULIMIT 2 "Feb 1, 2003"
NAME
ulimit - get and set process limits
SYNOPSIS

#include <ulimit.h>

long ulimit(int cmd, /* newlimit */...);
DESCRIPTION

The ulimit() function provides for control over process limits. It is effective in limiting the growth of regular files. Pipes are limited to PIPE_MAX bytes.

The cmd values, defined in <ulimit.h>, include: UL_GETFSIZE

Return the soft file size limit of the process. The limit is in units of 512-byte blocks and is inherited by child processes. Files of any size can be read. The return value is the integer part of the soft file size limit divided by 512. If the result cannot be represented as a long int, the result is unspecified.

UL_SETFSIZE

Set the hard and soft file size limits for output operations of the process to the value of the second argument, taken as a long int. Any process may decrease its own hard limit, but only a process with appropriate privileges may increase the limit. The new file size limit is returned. The hard and soft file size limits are set to the specified value multiplied by 512. If the result would overflow an rlimit_t, the actual value set is unspecified.

UL_GMEMLIM

Get the maximum possible break value (see brk(2)).

UL_GDESLIM

Get the current value of the maximum number of open files per process configured in the system.

RETURN VALUES

Upon successful completion, ulimit() returns the value of the requested limit. Otherwise, -1 is returned, the limit is not changed, and errno is set to indicate the error.

ERRORS

The ulimit() function will fail if: EINVAL

The cmd argument is not valid.

EPERM

A process that has not asserted {PRIV_SYS_RESOURCE} in its effective set is trying to increase its file size limit.

USAGE

Since all return values are permissible in a successful situation, an application wishing to check for error situations should set errno to 0, then call ulimit(), and if it returns -1, check if errno is non-zero.

The getrlimit() and setrlimit() functions provide a more general interface for controlling process limits, and are preferred over ulimit(). See getrlimit(2).

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Standard
SEE ALSO

brk(2), getrlimit(2), write(2), attributes(5), privileges(5), standards(5)