Comment 4 for bug 271606

Many GNU utilities have more detailed info documentation than man pages. The See Also section of the sed man page is very clear about this.

  info sed Invoking

provides more information about the use of the sed options, including -i and that suffix. This information includes substitution for * , and so forth, which is not addressed at all by the suggested statements to "improve" the man page in this bug report.

If it is really felt to be necessary to add this information to the man page (as well as the info database, where the information already exists and which is already pointed to by the man page) please do be sure to add correct information to the man page!

My instinct is that anyone using sed deeply enough to use the -i[SUFFIX] option will be (or should be) using info sed rather than man sed to read the detailed sed documentation anyway :)