NetBSD-5.0.2/usr.bin/head/head.1

.\"	$NetBSD: head.1,v 1.12 2004/05/04 23:44:21 wiz Exp $
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.\"	from: @(#)head.1	8.1 (Berkeley) 6/6/93
.\"
.Dd May 4, 2004
.Dt HEAD 1
.Os
.Sh NAME
.Nm head
.Nd display first lines of a file
.Sh SYNOPSIS
.Nm
.Op Fl qv
.Op Fl n Ar count
.Op Fl c Ar byte_count
.Op Ar file ...
.Sh DESCRIPTION
This filter displays the first
.Ar count
lines of each of the specified files, or of the standard input if no
files are specified.
If
.Ar count
is omitted it defaults to 10.
If
.Fl c Ar byte_count
is specified,
.Nm
counts bytes instead of lines.
.Pp
If more than a single file is specified, or the
.Fl v
option is used, each file is preceded by a header consisting of the string
.Dq ==\*[Gt] XXX \*[Le]=
where
.Dq XXX
is the name of the file.
The
.Fl q
flag disables the printing of the header in all cases.
.Pp
The
.Nm
utility exits 0 on success, and \*[Gt]0 if an error occurs.
.Sh COMPATIBILITY
The historic command line syntax of
.Nm
is supported by this implementation.
.Pp
This command is mostly compatible with GNU extensions to
.Nm .
.Sh SEE ALSO
.Xr tail 1
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.2-92 .
.Sh HISTORY
The
.Nm
utility appeared in
.Bx 3.0 .
It was enhanced to include the
.Fl c ,
.Fl q ,
and
.Fl v
options for
.Nx 2.1 .