find-grep and complicated patterns

find-grep and complicated patterns

[Lennart Borgman]

find-grep is useful, but a bit hard with complicated patterns. How do 
you for example do something like this:

   find . -name "*.el" -type f -print0 | xargs -0 -e grep -nH -e "aaa bbb"

where there is a space in the pattern? The above does NOT work! Is this 
platform dependent? (On w32 you may use Cygwin or Gnuwin32+cmd.exe here.)

Re: find-grep and complicated patterns

[Miles Bader]

Lennart Borgman <lennart.borgman.073@student.lu.se> writes:
>    find . -name "*.el" -type f -print0 | xargs -0 -e grep -nH -e "aaa bbb"
>
> where there is a space in the pattern? The above does NOT work! Is this 
> platform dependent?

Apparently so because it works fine for me (debian)...

-Miles

-- 
Ich bin ein Virus. Mach' mit und kopiere mich in Deine .signature.

Re: find-grep and complicated patterns

[Eli Zaretskii]

> Date: Wed, 13 Dec 2006 03:35:07 +0100
> From: Lennart Borgman <lennart.borgman.073@student.lu.se>
> 
>    find . -name "*.el" -type f -print0 | xargs -0 -e grep -nH -e "aaa bbb"
> 
> where there is a space in the pattern? The above does NOT work! Is this 
> platform dependent? (On w32 you may use Cygwin or Gnuwin32+cmd.exe here.)

I suspect that this is a bug in the Windows port of xargs: when it
invokes Grep, the quotes are already stripped, and it fails to quote
them again.

But the only way to be sure that my guess is correct is to see what
arguments Grep sees.  I suggest to write a short test program that
displays its argv[] array, then invoke it instead of Grep, and see
what it says.

Re: find-grep and complicated patterns

[Jari Aalto]

Eli Zaretskii <eliz@gnu.org> writes:

> > Date: Wed, 13 Dec 2006 03:35:07 +0100
> > From: Lennart Borgman <lennart.borgman.073@student.lu.se>
> > 
> >    find . -name "*.el" -type f -print0 | xargs -0 -e grep -nH -e "aaa bbb"
> > 
> > where there is a space in the pattern? The above does NOT work! Is this 
> > platform dependent? (On w32 you may use Cygwin or Gnuwin32+cmd.exe here.)
> 
> I suspect that this is a bug in the Windows port of xargs: when it
> invokes Grep, the quotes are already stripped, and it fails to quote
> them again.

cmdproxy may treat them differently. At least:

        dos> echo foo | something
                  ====

is treated like

        "foo "

If there is no extra space before pipe(|) character:

        dos> echo foo|something

then it's treated like:

        "foo"

Jari