1.\" $NetBSD: ulimit.3,v 1.9 2010/04/30 05:09:23 jruoho Exp $ 2.\" 3.\" Copyright (c) 1999 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Klaus Klein. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd April 30, 2010 31.Dt ULIMIT 3 32.Os 33.Sh NAME 34.Nm ulimit 35.Nd get and set process limits 36.Sh LIBRARY 37.Lb libc 38.Sh SYNOPSIS 39.In ulimit.h 40.Ft long int 41.Fn ulimit "int cmd" ... 42.Sh DESCRIPTION 43The 44.Fn ulimit 45function provides a method to query or alter resource limits of the calling 46process. 47The method to be performed is specified by the 48.Fa cmd 49argument; possible values are: 50.Bl -tag -width UL_GETFSIZEXX 51.It Li UL_GETFSIZE 52Return the soft file size limit of the process. 53The value returned is in units of 512-byte blocks. 54If the result cannot be represented in an object of type 55.Fa long int , 56the result is unspecified. 57.It Li UL_SETFSIZE 58Set the hard and soft file size limits of the process to the value of the 59second argument passed, which is in units of 512-byte blocks, and which is 60expected to be of type 61.Fa long int . 62The new file size limit of the process is returned. 63Any process may decrease the limit, but raising it is only permitted if 64the caller is the super-user. 65.El 66.Pp 67If successful, the 68.Fn ulimit 69function will not change the setting of 70.Va errno . 71.Sh RETURN VALUES 72If successful, the 73.Fn ulimit 74function returns the value of the requested limit. 75Otherwise, it returns \-1, sets 76.Va errno 77to indicate an error, and the limit is not changed. 78Therefore, to detect an error condition applications should set 79.Va errno 80to 0, call 81.Fn ulimit , 82and check if \-1 is returned and 83.Va errno 84is non-zero. 85.Sh ERRORS 86The 87.Fn ulimit 88function will fail if: 89.Bl -tag -width Er 90.It Bq Er EINVAL 91The 92.Fa cmd 93argument is not valid. 94.It Bq Er EPERM 95It was attempted to increase a limit, and the caller is not the super-user. 96.El 97.Sh SEE ALSO 98.Xr getrlimit 2 , 99.Xr setrlimit 2 100.Sh STANDARDS 101The 102.Fn ulimit 103function conforms to 104.St -xsh5 105and 106.St -p1003.1-2001 . 107It was marked as obsolete in the 108.St -p1003.1-2008 109revision, which recommended the use of 110.Xr getrlimit 2 111and 112.Xr setrlimit 2 113instead, noting that because 114.Fn ulimit 115uses the type 116.Vt long 117rather than 118.Vt rlim_t , 119it may not be sufficient for file sizes on many current systems. 120