xref: /freebsd/usr.bin/head/head.1 (revision 5f4c09dd85bff675e0ca63c55ea3c517e0fddfcc)
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28.\"	@(#)head.1	8.1 (Berkeley) 6/6/93
29.\"
30.Dd June 12, 2022
31.Dt HEAD 1
32.Os
33.Sh NAME
34.Nm head
35.Nd display first lines of a file
36.Sh SYNOPSIS
37.Nm
38.Op Fl qv
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.Pp
63Both
64.Ar count
65and
66.Ar bytes
67may also be specified with size suffixes supported by
68.Xr expand_number 3 .
69.It Fl q , Fl -quiet , Fl -silent
70Suppresses printing of headers when multiple files are being examined.
71.It Fl v , Fl -verbose
72Prepend each file with a header.
73.El
74.Pp
75If more than a single file is specified, or if the
76.Fl v
77option is used, each file is preceded by a
78header consisting of the string
79.Dq ==> XXX <==
80where
81.Dq XXX
82is the name of the file.
83The
84.Fl q
85flag disables the printing of the header in all cases.
86.Sh EXIT STATUS
87.Ex -std
88.Sh EXAMPLES
89To display the first 500 lines of the file
90.Ar foo :
91.Pp
92.Dl $ head -n 500 foo
93.Pp
94.Nm
95can be used in conjunction with
96.Xr tail 1
97in the following way to, for example, display only line 500 from the file
98.Ar foo :
99.Pp
100.Dl $ head -n 500 foo | tail -n 1
101.Sh SEE ALSO
102.Xr tail 1 ,
103.Xr expand_number 3
104.Sh HISTORY
105The
106.Nm
107command appeared in PWB UNIX.
108