Re: grep -v broken for large pattern lists

[Jim Meyering]

Rob Robason wrote:
> running the command
>
> grep -v -F -f pattern-file search-file
>
> with a large pattern-file (in my case 1234 patterns) fails to yield the
> complement of the same command less the -v option. The result is the same
> without the -F option, though _much_ slower.
>
> The patterns I'm using are of the form:
> address@hidden
> My search-file has about 4900 lines of the form:
> 01011: address@hidden
> 20090704T062201    20071105T170000    20071105T173000    norecur    0
> Wrap up after brainstorming Friday
>
> A workaround would be appreciated, since I was really counting on grep -v
> working properly for what I'm trying to do.

Thanks for the report.

It'd help if you would provide a complete example
and mention what version of grep you're using:

    - run "grep --version" if you built it yourself,
    - or "rpm -q grep" if it's on an rpm-based distro,
    - or something like "dpkg -l grep" on a deb-based system.

However, the best would be if you can build and retest
using the latest from the upstream git repository:

It's here:
    http://git.savannah.gnu.org/cgit/grep.git/

Build via this:
    git clone git://git.sv.gnu.org/grep.git &&
    cd grep && ./bootstrap && /configure && make && make check

Then, confirm that your complete example still fails when using
the just-built src/grep.