1.\" Copyright (c) 1980, 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 3. All advertising materials mentioning features or use of this software 14.\" must display the following acknowledgement: 15.\" This product includes software developed by the University of 16.\" California, Berkeley and its contributors. 17.\" 4. Neither the name of the University nor the names of its contributors 18.\" may be used to endorse or promote products derived from this software 19.\" without specific prior written permission. 20.\" 21.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31.\" SUCH DAMAGE. 32.\" 33.\" @(#)nice.1 8.1 (Berkeley) 6/6/93 34.\" 35.Dd June 6, 1993 36.Dt NICE 1 37.Os BSD 4 38.Sh NAME 39.Nm nice 40.Nd execute a command at a low scheduling priority 41.Sh SYNOPSIS 42.Nm nice 43.Op Fl Ns Ar number 44.Ar command 45.Op Ar arguments 46.Sh DESCRIPTION 47.Nm Nice 48runs 49.Ar command 50at a low priority. 51(Think of low and slow). 52If 53.Fl Ns Ar number 54is specified, and if it is greater than or equal 55to 10 (the default), 56.Nm nice 57will execute 58.Ar command 59at that priority. 60The upper bound, or lowest priority that 61.Nm nice 62will run a command is 20. 63The lower bounds or 64higher priorities (integers less than 10) 65can only be requested by the super-user. 66Negative numbers are expressed as 67.Fl - Ns Ar number . 68.Pp 69The returned exit status is the exit value from the 70command executed by 71.Nm nice . 72.Sh SEE ALSO 73.Xr csh 1 , 74.Xr renice 8 75.Sh HISTORY 76A 77.Nm nice 78command appeared in 79.At v6 . 80.Sh BUGS 81.Nm Nice 82is particular to 83.Xr sh 1 . 84If you use 85.Xr csh 1 , 86then commands executed with ``&'' are automatically immune to hangup 87signals while in the background. 88.Pp 89.Nm Nice 90is built into 91.Xr csh 1 92with a slightly different syntax than described here. The form 93.Ql nice +10 94nices to positive nice, and 95.Ql nice \-10 96can be used 97by the super-user to give a process more of the processor. 98