xref: /freebsd/usr.bin/xargs/xargs.1 (revision 0de89efe5c443f213c7ea28773ef2dc6cf3af2ed)
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36.\"	@(#)xargs.1	8.1 (Berkeley) 6/6/93
37.\"
38.Dd June 6, 1993
39.Dt XARGS 1
40.Os
41.Sh NAME
42.Nm xargs
43.Nd "construct argument list(s) and execute utility"
44.Sh SYNOPSIS
45.Nm xargs
46.Op Fl 0
47.Op Fl t
48.Oo Op Fl x
49.Fl n Ar number
50.Oc
51.Op Fl s Ar size
52.Op Ar utility Op Ar arguments ...
53.Sh DESCRIPTION
54The
55.Nm
56utility reads space, tab, newline and end-of-file delimited arguments
57from the standard input and executes the specified
58.Ar utility
59with them as
60arguments.
61.Pp
62The utility and any arguments specified on the command line are given
63to the
64.Ar utility
65upon each invocation, followed by some number of the arguments read
66from standard input.
67The
68.Ar utility
69is repeatedly executed until standard input is exhausted.
70.Pp
71Spaces, tabs and newlines may be embedded in arguments using single
72(``\ '\ '')
73.Ek
74or double (``"'') quotes or backslashes (``\e'').
75Single quotes escape all non-single quote characters, excluding newlines,
76up to the matching single quote.
77Double quotes escape all non-double quote characters, excluding newlines,
78up to the matching double quote.
79Any single character, including newlines, may be escaped by a backslash.
80.Pp
81The options are as follows:
82.Bl -tag -width indent
83.It Fl 0
84Changes
85.Nm
86to expect NUL
87(``\\0'')
88characters as seperators, instead of spaces and newlines.
89This is expected to be used in concert with the
90.Fl print0
91function in
92.Nm find .
93.It Fl n Ar number
94Set the maximum number of arguments taken from standard input for each
95invocation of the utility.
96An invocation of
97.Ar utility
98will use less than
99.Ar number
100standard input arguments if the number of bytes accumulated (see the
101.Fl s
102option) exceeds the specified
103.Ar size
104or there are fewer than
105.Ar number
106arguments remaining for the last invocation of
107.Ar utility .
108The current default value for
109.Ar number
110is 5000.
111.It Fl s Ar size
112Set the maximum number of bytes for the command line length provided to
113.Ar utility .
114The sum of the length of the utility name and the arguments passed to
115.Ar utility
116(including
117.Dv NULL
118terminators) will be less than or equal to this number.
119The current default value for
120.Ar size
121is
122.Dv ARG_MAX
123- 2048.
124.It Fl t
125Echo the command to be executed to standard error immediately before it
126is executed.
127.It Fl x
128Force
129.Nm
130to terminate immediately if a command line containing
131.Ar number
132arguments will not fit in the specified (or default) command line length.
133.El
134.Pp
135If no
136.Ar utility
137is specified,
138.Xr echo 1
139is used.
140.Pp
141Undefined behavior may occur if
142.Ar utility
143reads from the standard input.
144.Pp
145The
146.Nm
147utility exits immediately (without processing any further input) if a
148command line cannot be assembled,
149.Ar utility
150cannot be invoked, an invocation of the utility is terminated by a signal
151or an invocation of the utility exits with a value of 255.
152.Pp
153The
154.Nm
155utility exits with a value of 0 if no error occurs.
156If
157.Ar utility
158cannot be invoked,
159.Nm
160exits with a value of 127.
161If any other error occurs,
162.Nm
163exits with a value of 1.
164.Sh SEE ALSO
165.Xr echo 1 ,
166.Xr find 1
167.Sh STANDARDS
168The
169.Nm
170utility is expected to be
171.St -p1003.2
172compliant.
173