1.\" Copyright (c) 1990, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" John B. Roll Jr. and the Institute of Electrical and Electronics 6.\" Engineers, Inc. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. All advertising materials mentioning features or use of this software 17.\" must display the following acknowledgement: 18.\" This product includes software developed by the University of 19.\" California, Berkeley and its contributors. 20.\" 4. Neither the name of the University nor the names of its contributors 21.\" may be used to endorse or promote products derived from this software 22.\" without specific prior written permission. 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34.\" SUCH DAMAGE. 35.\" 36.\" @(#)xargs.1 8.1 (Berkeley) 6/6/93 37.\" $FreeBSD$ 38.\" 39.Dd June 6, 1993 40.Dt XARGS 1 41.Os 42.Sh NAME 43.Nm xargs 44.Nd "construct argument list(s) and execute utility" 45.Sh SYNOPSIS 46.Nm 47.Op Fl 0 48.Oo 49.Fl n Ar number 50.Op Fl x 51.Oc 52.Op Fl s Ar size 53.Op Fl t 54.Op Ar utility Op Ar argument ... 55.Sh DESCRIPTION 56The 57.Nm 58utility reads space, tab, newline and end-of-file delimited arguments 59from the standard input and executes the specified 60.Ar utility 61with them as 62arguments. 63.Pp 64The utility and any arguments specified on the command line are given 65to the 66.Ar utility 67upon each invocation, followed by some number of the arguments read 68from standard input. 69The 70.Ar utility 71is repeatedly executed until standard input is exhausted. 72.Pp 73Spaces, tabs and newlines may be embedded in arguments using single 74(``\ '\ '') 75or double (``"'') quotes or backslashes (``\e''). 76Single quotes escape all non-single quote characters, excluding newlines, 77up to the matching single quote. 78Double quotes escape all non-double quote characters, excluding newlines, 79up to the matching double quote. 80Any single character, including newlines, may be escaped by a backslash. 81.Pp 82The options are as follows: 83.Bl -tag -width indent 84.It Fl 0 85Change 86.Nm 87to expect NUL 88(``\\0'') 89characters as separators, instead of spaces and newlines. 90This is expected to be used in concert with the 91.Fl print0 92function in 93.Xr find 1 . 94.It Fl n Ar number 95Set the maximum number of arguments taken from standard input for each 96invocation of the utility. 97An invocation of 98.Ar utility 99will use less than 100.Ar number 101standard input arguments if the number of bytes accumulated (see the 102.Fl s 103option) exceeds the specified 104.Ar size 105or there are fewer than 106.Ar number 107arguments remaining for the last invocation of 108.Ar utility . 109The current default value for 110.Ar number 111is 5000. 112.It Fl s Ar size 113Set the maximum number of bytes for the command line length provided to 114.Ar utility . 115The sum of the length of the utility name, the arguments passed to 116.Ar utility 117(including 118.Dv NULL 119terminators) and the current environment will be less than or equal to 120this number. 121The current default value for 122.Ar size 123is 124.Dv ARG_MAX 125- 4096. 126.It Fl t 127Echo the command to be executed to standard error immediately before it 128is executed. 129.It Fl x 130Force 131.Nm 132to terminate immediately if a command line containing 133.Ar number 134arguments will not fit in the specified (or default) command line length. 135.El 136.Pp 137If no 138.Ar utility 139is specified, 140.Xr echo 1 141is used. 142.Pp 143Undefined behavior may occur if 144.Ar utility 145reads from the standard input. 146.Pp 147The 148.Nm 149utility exits immediately (without processing any further input) if a 150command line cannot be assembled, 151.Ar utility 152cannot be invoked, an invocation of the utility is terminated by a signal 153or an invocation of the utility exits with a value of 255. 154.Pp 155The 156.Nm 157utility exits with a value of 0 if no error occurs. 158If 159.Ar utility 160cannot be invoked, 161.Nm 162exits with a value of 127. 163If any other error occurs, 164.Nm 165exits with a value of 1. 166.Sh SEE ALSO 167.Xr echo 1 , 168.Xr find 1 , 169.Xr execvp 3 170.Sh STANDARDS 171The 172.Nm 173utility is expected to be 174.St -p1003.2 175compliant. 176.Sh BUGS 177If 178.Ar utility 179attempts to invoke another command such that the number of arguments or the 180size of the environment is increased, it risks 181.Xr execvp 3 182failing with 183.Er E2BIG . 184