SysIII/usr/src/man/man1/tail.1

.TH TAIL 1
.SH NAME
tail \- deliver the last part of a file
.SH SYNOPSIS
.B tail
[
.RB \(+-[number][ lbc ]
[
.B \-f
] ] [ file ]
.SH DESCRIPTION
.I Tail\^
copies the named file to the standard output beginning
at a designated place.
If no file is named, the standard input is used.
.PP
Copying begins at distance
.BI + number\^
from the beginning, or
.BI \- number\^
from the end of the input
(if
.I number\^
is null, the value 10 is assumed).
.I Number\^
is counted in units of lines, blocks, or characters,
according to the appended option
.BR l ,
.BR b ,
or
.BR c .
When no units are specified, counting is by lines.
.PP
With the
.B \-f
(``follow'') option, if the input file is not a pipe,
the program will not terminate after the line of the input
file has been copied, but will enter an endless loop, wherein it
sleeps for a second and then attempts to read and copy
further records from the input file.
Thus it may be used to monitor the growth of a file that is
being written by some other process.
For example, the command:
.PP
.RS
tail \|\-f \|fred
.RE
.PP
will print the last ten lines of the file
.BR fred ,
followed by any lines that are appended to
.B fred\^
between the time
.I tail\^
is initiated and killed.
.SH SEE ALSO
dd(1).
.SH BUGS
Tails relative to the end of the file
are treasured up in a buffer, and thus
are limited in length.
Various kinds of anomalous behavior may happen
with character special files.