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

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.\"	@(#)head.1	8.1 (Berkeley) 6/6/93
.\" $FreeBSD$
.\"
.Dd April 10, 2018
.Dt HEAD 1
.Os
.Sh NAME
.Nm head
.Nd display first lines of a file
.Sh SYNOPSIS
.Nm
.Op Fl n Ar count | Fl c Ar bytes
.Op Ar
.Sh DESCRIPTION
This filter displays the first
.Ar count
lines or
.Ar bytes
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.
.Pp
The following options are available:
.Bl -tag -width indent
.It Fl c Ar bytes , Fl -bytes Ns = Ns Ar bytes
Print
.Ar bytes
of each of the specified files.
.It Fl n Ar count , Fl -lines Ns = Ns Ar count
Print
.Ar count
lines of each of the specified files.
.El
.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
.Sh SEE ALSO
.Xr tail 1
.Sh HISTORY
The
.Nm
command appeared in PWB UNIX.