gno/bin/tail/tail.1

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.\"	@(#)tail.1	2.0 (GNO) 8/1/97
.\"
.TH TAIL 1 "August 1997" "GNO" "Commands and Applications"
.SH NAME
.BR tail
\- display the last part of a file
.SH SYNOPSIS
.BR tail
.RB [ -f ]
.RB [ -b
.IR number " |"
.B -c
.IR number " |"
.B -n
.IR number ]
.RI [ file ...]
.SS Obsolescent:
.BR tail "
.RB [ -f ]
.RB [ + | -\fInumber [ l
.RB "| " b " | " c ]]
.RI [ file ...]
.SH DESCRIPTION
The
.BR tail
utility displays the contents of
.BR file
or, by default, its standard input, to the standard output.
.LP
The display begins at a byte, line or 512-byte block location in the
input.
Numbers having a leading plus (``+'') sign are relative to the beginning
of the input, for example,
.B "-c +2"
starts the display at the second
byte of the input.
Numbers having a leading minus (``-'') sign or no explicit sign are
relative to the end of the input, for example,
.B "-n 2"
displays the last two lines of the input.
The default starting location is
.BR "-n 10" ,
or the last 10 lines of the input.
.LP
.SH OPTIONS
The options are as follows:
.RS
.IP \fB-b\fR \fInumber\fR
The location is
.IR number
512-byte blocks.
.IP \fB-c\fR \fInumber\fR
The location is
.IR number
bytes.
.IP \fB-f\fR
The
.B -f
option causes
.BR tail
not to stop when end of file is reached, but rather to wait for additional
data to be appended to the input.
The
.B -f
option is ignored if the standard input is a pipe, but not if it is a FIFO.
.IP \fB-n\fR \fInumber\fR
The location is
.IR number
lines.
.RE
.LP
If more than a single file is specified, each file is preceded by a
header consisting of the string
.B "==> XXX <=="
where
.B XXX
is the name of the file.
.LP
The
.BR tail
utility exits 0 on success, and >0 if an error occurs.
.SH ATTRIBUTIONS
This command was ported from FreeBSD source code
for distribution with GNO/ME 2.0.6.
.SH SEE ALSO
.BR cat (1),
.BR head (1),
.BR sed (1)
.SH STANDARDS
The
.BR tail
utility is expected to be a superset of the POSIX.2
specification.
In particular, the
.BR -b
option is an extension to that standard.
.LP
The historic (obsolescent) command line syntax of
.BR tail
is supported by this implementation.
.SH HISTORY
The BSD
.B -r
option, which causes the input to be displayed in reverse order, by line,
has not been implemented for the GNO version of
.BR tail .
.PP
Version 1.1 (18-Jan-93) of
.BR tail ,
shipped with GNO 2.0, was written by Sameer Parekh (zane@ddsw1.MCS.COM).