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       logtail - print log file lines that have not been read


       logtail [-t] -flogfile [-ooffsetfile]


       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.


       -f     logfile to be read after offset

       -o     offsetfile stores offset of previous run

       -t     test mode - do not change offset in offsetfile


       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


       The   original   logtail   was   written  in  C  by  Craig  H.  Rowland
       <>.   This   version   of   logtail   is   a   Perl
       reimplementation  by  Paul Slootman <>.  Enhanced by the
       Debian Logcheck Team <>.

       This manual was written by Oohara Yuuma <>.