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Warning: this routine is obsolete.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.
UL_GETFSIZE
Return the limit on the size of a file, in units of 512 bytes.
UL_SETFSIZE
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 max-
imum number of files that the calling process can open.
RETURN VALUE
On success, ulimit() returns a nonnegative value. On error, -1 is re-
turned, and errno is set to indicate the error.
ERRORS
EPERM 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)
Linux man-pages 6.9.1 2024-05-02 ulimit(3)
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