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.\"	$OpenBSD: head.1,v 1.21 2014/12/15 20:31:40 tedu Exp $
.\"
.\" Copyright (c) 1980, 1990 The Regents of the University of California.
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\"	from: @(#)head.1	6.6 (Berkeley) 7/24/91
.\"
.Dd $Mdocdate: December 15 2014 $
.Dt HEAD 1
.Os
.Sh NAME
.Nm head
.Nd display first few lines of files
.Sh SYNOPSIS
.Nm head
.Op Fl Ns Ar count | Fl n Ar count
.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 Fl Ns Ar count | Fl n Ar count
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 -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 -1
.Sh SEE ALSO
.Xr cat 1 ,
.Xr cut 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 syntax
.Fl Ns Ar count
is supported by this implementation.
.Sh HISTORY
The
.Nm
utility first appeared in
.Bx 1 .
.Sh AUTHORS
.An Bill Joy ,
August 24, 1977.