tac − concatenate and print files in reverse
tac [OPTION]... [FILE]...
Write each FILE to standard output, last line first. With no FILE, or when FILE is −, read standard input.
arguments to long options are mandatory for short options
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
GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Report tac translation bugs to <http://translationproject.org/team/>
Written by Jay Lepreau and David MacKenzie.
© 2013 Free Software Foundation, Inc. License GPLv3+:
GNU GPL version 3 or later
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
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.