'\" t .\" Copyright (C) 1996 Andries Brouwer (aeb@cwi.nl) .\" .\" SPDX-License-Identifier: Linux-man-pages-copyleft .\" .\" Moved to man3, aeb, 980612 .\" .TH ulimit 3 2023-07-20 "Linux man-pages 6.05.01" .SH NAME ulimit \- get and set user limits .SH LIBRARY Standard C library .RI ( libc ", " \-lc ) .SH SYNOPSIS .nf .B #include .PP .BI "[[deprecated]] long ulimit(int " cmd ", long " newlimit ); .fi .SH DESCRIPTION Warning: this routine is obsolete. Use .BR getrlimit (2), .BR setrlimit (2), and .BR sysconf (3) instead. For the shell command .BR ulimit , see .BR bash (1). .PP The .BR ulimit () call will get or set some limit for the calling process. The .I cmd argument can have one of the following values. .TP .B UL_GETFSIZE Return the limit on the size of a file, in units of 512 bytes. .TP .B UL_SETFSIZE Set the limit on the size of a file. .TP .B 3 (Not implemented for Linux.) Return the maximum possible address of the data segment. .TP .B 4 (Implemented but no symbolic constant provided.) Return the maximum number of files that the calling process can open. .SH RETURN VALUE On success, .BR ulimit () returns a nonnegative value. On error, \-1 is returned, and .I errno is set to indicate the error. .SH ERRORS .TP .B EPERM An unprivileged process tried to increase a limit. .SH ATTRIBUTES For an explanation of the terms used in this section, see .BR attributes (7). .TS allbox; lbx lb lb l l l. Interface Attribute Value T{ .na .nh .BR ulimit () T} Thread safety MT-Safe .TE .sp 1 .SH STANDARDS POSIX.1-2008. .SH HISTORY SVr4, POSIX.1-2001. POSIX.1-2008 marks it as obsolete. .SH SEE ALSO .BR bash (1), .BR getrlimit (2), .BR setrlimit (2), .BR sysconf (3)