xref: /freebsd/usr.bin/head/head.1 (revision 43a5ec4eb41567cc92586503212743d89686d78f)
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28.\"	@(#)head.1	8.1 (Berkeley) 6/6/93
29.\" $FreeBSD$
30.\"
31.Dd April 10, 2018
32.Dt HEAD 1
33.Os
34.Sh NAME
35.Nm head
36.Nd display first lines of a file
37.Sh SYNOPSIS
38.Nm
39.Op Fl n Ar count | Fl c Ar bytes
40.Op Ar
41.Sh DESCRIPTION
42This filter displays the first
43.Ar count
44lines or
45.Ar bytes
46of each of the specified files, or of the standard input if no
47files are specified.
48If
49.Ar count
50is omitted it defaults to 10.
51.Pp
52The following options are available:
53.Bl -tag -width indent
54.It Fl c Ar bytes , Fl -bytes Ns = Ns Ar bytes
55Print
56.Ar bytes
57of each of the specified files.
58.It Fl n Ar count , Fl -lines Ns = Ns Ar count
59Print
60.Ar count
61lines of each of the specified files.
62.El
63.Pp
64If more than a single file is specified, each file is preceded by a
65header consisting of the string
66.Dq ==> XXX <==
67where
68.Dq XXX
69is the name of the file.
70.Sh EXIT STATUS
71.Ex -std
72.Sh EXAMPLES
73To display the first 500 lines of the file
74.Ar foo :
75.Pp
76.Dl $ head -n 500 foo
77.Pp
78.Nm
79can be used in conjunction with
80.Xr tail 1
81in the following way to, for example, display only line 500 from the file
82.Ar foo :
83.Pp
84.Dl $ head -n 500 foo | tail -n 1
85.Sh SEE ALSO
86.Xr tail 1
87.Sh HISTORY
88The
89.Nm
90command appeared in PWB UNIX.
91