On Tue, Aug 23, 2022 at 09:50:20AM +0900, Dominique Martinet wrote:
> Dave Close wrote on Mon, Aug 22, 2022 at 03:01:11PM -0700:
> > $ grep CALL ./* | wc
> > 16325 61444 950870
> > $ grep CALL $( ls ./* ) | wc
> > 16375 61601 953451
> >
> > So I almost have a solution. Except the extra 50 lines found in the
> > second command are disturbing. Thus far, it appears that those lines
> > are duplicates and some of the duplicated lines are from files with
> > names that do not contain any special characters.
>
> That is because this is not correct either.
> Just don't use ls for thing, `find -print0` is just about the only thing
> that can handle arbitrary filenames (well, direct shell expansions also
> mostly work with care; but I'll assume your example is oversimplified
> otherwise you wouldn't be trying to use ls... right?)
>
...
The output of ls is not guaranteed to be stable.
Moreover, there will be problems when files contain spaces.
> As for quoting:
...
The shell does expansions, like $(...) and after that, it does 'Quote Removal'.
A quote(!) from the manpage of bash:
Quote Removal
After the preceding expansions, all unquoted occurrences of the
characters \, ', and " that did not result from one of the
above expansions are removed.
> Anyway, here's an example for find -print0:
>
> $ find . -type f -print0 | xargs -0 grep a --
> ./one one:a
> ./one:a
>
> --
> Dominique
find is the path to go.
--
Regards, Mike Jonkmans
