Drew Adams írta:
>
> In Emacs 22 you can pipe the output of one grep to another: grep foo|grep
> bar|grep toto. Just type that at the grep prompt.
>
> You might also be interested in Icicles command `icicle-compilation-search'
> (`C-c `' in buffer *grep*), which lets you search among grep hits using
> additional regexps -
> http://www.emacswiki.org/cgi-bin/wiki/Icicles_-_Other_Search_Commands.

Thanks, but none of these are what I need.

I don't want to combine two grep commands. I want to run two completely
different ones  with the ability to restore the results of the first
after I'm finished with the second.