TAC(1)

📦
version 9.10 · 5 versions
, in ubuntu stonking

💅 TAC(1) — the reverse-girlie manual page

okay so you're in section User Commands of the manual and the whole page is about tac — which is literally cat spelled backwards. bestie, the naming committee ate that day and they knew it. 🐱✨

✨ NAME ✨

tac — concatenate and print files in reverse 🦋

✨ SYNOPSIS ✨

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

✨ DESCRIPTION ✨

So here's the vibe: tac writes each FILE to standard output, but it does it last line first. That's it. That's the whole personality. It's giving "read my diary but from the end so it hits different." 🔥

If you hand it no FILE at all, or if a FILE is literally just -, it reads from standard input. Yes, the classic - move. icon behavior, no notes. 💅

ok real talk for a sec: mandatory arguments to long options are mandatory for short options too. Translation — if a long option needs a value, its short twin needs that same value. Don't skip it, bestie, it won't guess. 😭
  • -b, --before — attaches the separator before the thing instead of after it 🎀
  • -r, --regex — treats the separator as a regular expression (yes, fr fr, regex in your reverse-file tool, we love range) ⭐
  • -s, --separator=*STRING* — uses STRING as the separator instead of the newline 🌸
  • --help — prints this help and dips out 👋
  • --version — outputs version info and dips out 👑

And one (1) lore drop you need in your notes app: non-seekable input is buffered to $TMPDIR, defaulting to /tmp. So yeah, if your input is the kind of thing you can't scrub back and forth through, it's gonna camp out in your temp dir first. iykyk. 🏕️💖

✨ AUTHOR ✨

Written by Jay Lepreau and David MacKenzie. legends, honestly. 🫶

✨ REPORTING BUGS ✨

Found a lil glitch? Don't suffer in silence, tell the girlies:

✨ SEE ALSO ✨

  • cat(1) — the OG, the forwards one, the prequel 🌈
  • rev(1) — reverses characters, not lines. different girl, same energy 💀

Full documentation <https://www.gnu.org/software/coreutils/tac> or available locally via: info '(coreutils) tac invocation'

Packaged by Ubuntu (9.10-1ubuntu2) 💜 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.

and that's the page, bestie!! GNU coreutils 9.10, August 2026, shipped as TAC(1) in section 1. now go print something backwards and feel something. mwah. 🎀💖✨
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