NAME¶
logtail - print log file lines that have not been read
SYNOPSIS¶
logtail [-t]
-flogfile [-o
offsetfile]
DESCRIPTION¶
logtail reads a specified file (usually a log file) and writes to the
standard output that part of it which has not been read by previous runs of
logtail. It prints the appropriate number of bytes from the end of
logfile, assuming that all changes that are made to it are to add new
characters to it.
logfile must be a plain file. A symlink is not allowed.
logtail stores the information about how much of it has already been read
in a separate file called
offsetfile.
offsetfile can be omitted.
If omitted, the file named
logfile.offset in the same directory which
contains
logfile is used by default.
If
offsetfile is not empty, the inode of
logfile is checked. If
the inode is changed,
logtail simply prints the entire file. If the
inode is not changed but
logfile is shorter than it was at the last run
of
logtail, it writes a warning message to the standard output.
OPTIONS¶
- -f
- logfile to be read after offset
- -o
- offsetfile stores offset of previous run
- -t
- test mode - do not change offset in offsetfile
RETURN VALUES¶
- 0
- successful
- 65
- cannot get the size of logfile
- 66
- logfile does not exist, is not a plain file, or is
not readable
- 73
- cannot write offsetfile
AUTHOR¶
The original
logtail was written in C by Craig H. Rowland
<crowland@psionic.com>. This version of
logtail is a Perl
reimplementation by Paul Slootman <paul@debian.org>. Enhanced by the
Debian Logcheck Team <logcheck-devel@lists.alioth.debian.org>.
This manual was written by Oohara Yuuma <oohara@libra.interq.or.jp>.
SEE ALSO¶
logcheck(8)
