xref: /openbsd/usr.bin/head/head.1 (revision 3d8817e4)
1.\"	$OpenBSD: head.1,v 1.17 2010/09/03 11:09:29 jmc Exp $
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30.\"	from: @(#)head.1	6.6 (Berkeley) 7/24/91
31.\"
32.Dd $Mdocdate: September 3 2010 $
33.Dt HEAD 1
34.Os
35.Sh NAME
36.Nm head
37.Nd display first few lines of files
38.Sh SYNOPSIS
39.Nm head
40.Oo
41.Fl Ns Ar count No \&|
42.Fl n Ar count
43.Oc
44.Op Ar
45.Sh DESCRIPTION
46The
47.Nm
48utility copies the first
49.Ar count
50lines of each specified
51.Ar file
52to the standard output.
53If no files are named,
54.Nm
55copies lines from the standard input.
56If
57.Ar count
58is omitted, it defaults to 10.
59.Pp
60The options are as follows:
61.Bl -tag -width Ds
62.It Xo Fl Ns Ar count No \&|
63.Fl n Ar count
64.Xc
65Copy the first
66.Ar count
67lines of each input file to the standard output.
68.Ar count
69must be a positive decimal integer.
70.El
71.Pp
72If more than one file is specified,
73.Nm
74precedes the output of each file with the following, in order to distinguish
75the head of each file:
76.Pp
77.Dl ==> Ar file No <==
78.Sh EXIT STATUS
79.Ex -std head
80.Sh EXAMPLES
81To display the first 500 lines of the file
82.Ar foo :
83.Pp
84.Dl $ head -500 foo
85.Pp
86.Nm
87can be used in conjunction with
88.Xr tail 1
89in the following way to, for example, display only line 500 from the file
90.Ar foo :
91.Pp
92.Dl $ head -500 foo | tail -1
93.Sh SEE ALSO
94.Xr cat 1 ,
95.Xr less 1 ,
96.Xr more 1 ,
97.Xr tail 1
98.Sh STANDARDS
99The
100.Nm
101utility is compliant with the
102.St -p1003.1-2008
103specification.
104.Pp
105The historic command line syntax is supported by this implementation.
106.Sh HISTORY
107The
108.Nm
109utility appeared in
110.Bx 3.0 .
111