tac(1)

NAME

tac - concatenate and print files in reverse

SYNOPSIS

tac [OPTION]... [FILE]...

DESCRIPTION

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.

-b, --before: attach the separator before instead of after

-r, --regex: interpret the separator as a regular expression

-s, --separator=STRING: use STRING as the separator instead of newline

--help: display this help and exit

--version: output version information and exit

Non-seekable input is buffered to $TMPDIR, defaulting to /tmp.

AUTHOR

Written by Jay Lepreau and David MacKenzie.

REPORTING BUGS

Report bugs to: <[email protected]>.
Report any translation bugs to: <https://translationproject.org/team/>.
GNU coreutils home page: <https://www.gnu.org/software/coreutils/>
General help using GNU software: <https://www.gnu.org/gethelp/>

COPYRIGHT

Copyright © 2026 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://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.