Ubuntu
sed package

  1. Bug #271606
  2. Comment #3

Comment 3 for bug 271606

Revision history for this message
Mackenzie Morgan (maco.m) wrote : Re: In sed, -ir options generate second file with r appended to end of name

So, what it actually says is:
-i[SUFFIX], --in-place[=SUFFIX]

              edit files in place (makes backup if extension supplied)

For someone new to manpages it might be a bit ambiguous, but man man states that [] mean it's optional, and the comment underneath the -i[SUFFIX] line does make it clear that adding a suffix will back it up. I suppose the unclear part is exactly what the backup will be named. That sort or requires extrapolating from the whole "why am i giving a suffix?" thing.

I'm going to mark this a string-fix and bitesize bug since changing a manpage string is simple enough.