ulimit - get and set user limits
long ulimit(int cmd, long newlimit);
Warning: this routine is obsolete. Use getrlimit(2), setrlimit(2),
and sysconf(3) instead. For the shell command ulimit, see
The ulimit() call will get or set some limit for the
calling process. The cmd argument can have one of the following
On success, ulimit() returns a nonnegative value. On error, -1 is
returned, and errno is set to indicate the error.
- Return the limit on the size of a file, in units of 512 bytes.
- Set the limit on the size of a file.
- (Not implemented for Linux.) Return the maximum possible address of the
- (Implemented but no symbolic constant provided.) Return the maximum number
of files that the calling process can open.
For an explanation of the terms used in this section, see attributes(7).
- An unprivileged process tried to increase a limit.
SVr4, POSIX.1-2001. POSIX.1-2008 marks ulimit() as obsolete.
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