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.\" $OpenBSD: head.1,v 1.17 2010/09/03 11:09:29 jmc Exp $
.\"
.\" Copyright (c) 1980, 1990 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" from: @(#)head.1 6.6 (Berkeley) 7/24/91
.\"
.Dd $Mdocdate: September 3 2010 $
.Dt HEAD 1
.Os
.Sh NAME
.Nm head
.Nd display first few lines of files
.Sh SYNOPSIS
.Nm head
.Oo
.Fl Ns Ar count No \&|
.Fl n Ar count
.Oc
.Op Ar
.Sh DESCRIPTION
The
.Nm
utility copies the first
.Ar count
lines of each specified
.Ar file
to the standard output.
If no files are named,
.Nm
copies lines from the standard input.
If
.Ar count
is omitted, it defaults to 10.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Xo Fl Ns Ar count No \&|
.Fl n Ar count
.Xc
Copy the first
.Ar count
lines of each input file to the standard output.
.Ar count
must be a positive decimal integer.
.El
.Pp
If more than one file is specified,
.Nm
precedes the output of each file with the following, in order to distinguish
the head of each file:
.Pp
.Dl ==> Ar file No <==
.Sh EXIT STATUS
.Ex -std head
.Sh EXAMPLES
To display the first 500 lines of the file
.Ar foo :
.Pp
.Dl $ head -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 -500 foo | tail -1
.Sh SEE ALSO
.Xr cat 1 ,
.Xr less 1 ,
.Xr more 1 ,
.Xr tail 1
.Sh STANDARDS
The
.Nm
utility is compliant with the
.St -p1003.1-2008
specification.
.Pp
The historic command line syntax is supported by this implementation.
.Sh HISTORY
The
.Nm
utility appeared in
.Bx 3.0 .
|
