SYNOPSIStac [options] file [...]
DESCRIPTION
The tac program prints the given files, but starting from the
end of file, in reverse line order. It is useful for quickly
examining the last few lines of a log file in most-recent order.
Available options are:
-s startexpr
Start printing at the first line that matches the given REX
expression. By default tac will start printing with the
last line of the file.
-e endexpr
End printing with the first line that matches the given REX
expression. By default tac will print until the start of
the file is reached. Note: Since tac reads the file
backwards by default, the startexpr will occur after
the endexpr in the original file, even though it appears
first in the output.
-n lines
Read at most this many lines from the file. This includes
any lines read but not printed before the startexpr
matches. It is a "safety limit" to avoid reading through all of
a very large log file if the start or end expressions are not
found.
-f
Read forward from the start of the file (like cat) instead
of backwards from the end.
EXAMPLE
Show all of today's web server hits from the log, since midnight.
Note that 13/Apr/1999 is yesterday's date:
tac -e '13/Apr/1999' /usr/local/httpd/logs/transfer.log
SEE ALSO
The Vortex readln function