xref: /freebsd/usr.bin/head/head.1 (revision 3c4ba5f55438f7afd4f4b0b56f88f2bb505fd6a6)
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28.\"	@(#)head.1	8.1 (Berkeley) 6/6/93
29.\" $FreeBSD$
30.\"
31.Dd June 12, 2022
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 qv
40.Op Fl n Ar count | Fl c Ar bytes
41.Op Ar
42.Sh DESCRIPTION
43This filter displays the first
44.Ar count
45lines or
46.Ar bytes
47of each of the specified files, or of the standard input if no
48files are specified.
49If
50.Ar count
51is omitted it defaults to 10.
52.Pp
53The following options are available:
54.Bl -tag -width indent
55.It Fl c Ar bytes , Fl -bytes Ns = Ns Ar bytes
56Print
57.Ar bytes
58of each of the specified files.
59.It Fl n Ar count , Fl -lines Ns = Ns Ar count
60Print
61.Ar count
62lines of each of the specified files.
63.Pp
64Both
65.Ar count
66and
67.Ar bytes
68may also be specified with size suffixes supported by
69.Xr expand_number 3 .
70.It Fl q , Fl -quiet , Fl -silent
71Suppresses printing of headers when multiple files are being examined.
72.It Fl v , Fl -verbose
73Prepend each file with a header.
74.El
75.Pp
76If more than a single file is specified, or if the
77.Fl v
78option is used, each file is preceded by a
79header consisting of the string
80.Dq ==> XXX <==
81where
82.Dq XXX
83is the name of the file.
84The
85.Fl q
86flag disables the printing of the header in all cases.
87.Sh EXIT STATUS
88.Ex -std
89.Sh EXAMPLES
90To display the first 500 lines of the file
91.Ar foo :
92.Pp
93.Dl $ head -n 500 foo
94.Pp
95.Nm
96can be used in conjunction with
97.Xr tail 1
98in the following way to, for example, display only line 500 from the file
99.Ar foo :
100.Pp
101.Dl $ head -n 500 foo | tail -n 1
102.Sh SEE ALSO
103.Xr tail 1 ,
104.Xr expand_number 3
105.Sh HISTORY
106The
107.Nm
108command appeared in PWB UNIX.
109