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ulimit(3) Library Functions Manual ulimit(3)

NAME

ulimit - get and set user limits

LIBRARY

Standard C library (libc, -lc)

SYNOPSIS

#include <ulimit.h>
[[deprecated]] long ulimit(int cmd, long newlimit);

DESCRIPTION

Warning: this routine is obsolete. Use getrlimit(2), setrlimit(2), and sysconf(3) instead. For the shell command ulimit, see bash(1).

The ulimit() call will get or set some limit for the calling process. The cmd argument can have one of the following values.

Return the limit on the size of a file, in units of 512 bytes.
Set the limit on the size of a file.
3
(Not implemented for Linux.) Return the maximum possible address of the data segment.
4
(Implemented but no symbolic constant provided.) Return the maximum number of files that the calling process can open.

RETURN VALUE

On success, ulimit() returns a nonnegative value. On error, -1 is returned, and errno is set to indicate the error.

ERRORS

An unprivileged process tried to increase a limit.

ATTRIBUTES

For an explanation of the terms used in this section, see attributes(7).

Interface Attribute Value
ulimit () Thread safety MT-Safe

STANDARDS

POSIX.1-2008.

HISTORY

SVr4, POSIX.1-2001. POSIX.1-2008 marks it as obsolete.

SEE ALSO

bash(1), getrlimit(2), setrlimit(2), sysconf(3)

2024-05-02 Linux man-pages (unreleased)