freebsd-dev/usr.bin/head/head.1

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.\" Copyright (c) 1980, 1990, 1993
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.\" may be used to endorse or promote products derived from this software
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.\" @(#)head.1 8.1 (Berkeley) 6/6/93
1999-08-28 01:08:13 +00:00
.\" $FreeBSD$
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.\"
.Dd March 16, 2013
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.Dt HEAD 1
.Os
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.Sh NAME
.Nm head
.Nd display first lines of a file
.Sh SYNOPSIS
.Nm
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.Op Fl n Ar count | Fl c Ar bytes
.Op Ar
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.Sh DESCRIPTION
This filter displays the first
.Ar count
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lines or
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.Ar bytes
of each of the specified files, or of the standard input if no
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files are specified.
If
.Ar count
is omitted it defaults to 10.
.Pp
If more than a single file is specified, each file is preceded by a
header consisting of the string
.Dq ==> XXX <==
where
.Dq XXX
is the name of the file.
.Sh EXIT STATUS
.Ex -std
.Sh EXAMPLES
To display the first 500 lines of the file
.Ar foo :
.Pp
.Dl $ head -n 500 foo
.Pp
.Nm
can be used in conjunction with
.Xr tail 1
in the following way to, for example, display only line 500 from the file
.Ar foo :
.Pp
.Dl $ head -n 500 foo | tail -n 1
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.Sh SEE ALSO
.Xr tail 1
.Sh HISTORY
The
.Nm
command appeared in PWB UNIX.