tac — concatenate and print files in reverse
Write each FILE to standard output, last line first. With no FILE, or when FILE is −, read standard input.
Mandatory arguments to long options are mandatory for short options too.
attach the separator before instead of after
interpret the separator as a regular expression
use STRING as the separator instead of newline
display this help and exit
output version information and exit
The full documentation for tac is maintained as a Texinfo manual. If the info and tac programs are properly installed at your site, the command
info coreutils 'tac invocation'
should give you access to the complete manual.
Copyright © 2014 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.