in reply to Re^4: FindBin works differently on Fedora Core 2? (replace)
in thread FindBin works differently on Fedora Core 2?

Sorry, I don't use FindBin (no one would ever guess that).

Once again we have an example of a feature that FindBin has but doesn't bother to export in a reusable manner (expanding symbolic links). 

    use File::Spec::Functions qw( rel2abs splitpath catpath );
    my $RealBin = $0;
    for( $RealBin ) {
        $_ = readlink($_) while -l $_;
        $_ = catpath( (splitpath rel2abs($_))[0,1] );
    }

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or 

    use File::Spec::Functions qw( rel2abs );
    use File::Basename qw( dirname );
    my $RealBin = $0;
    $RealBin = readlink($RealBin) while -l $RealBin;
    $RealBin = dirname( rel2abs($RealBin) );

[download]

and evidence that File::Spec could use some additions (realpath, basename, dirname).

- tye        

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Re^6: FindBin works differently on Fedora Core 2? (replace)
by PodMaster (Abbot) on Jun 08, 2004 at 17:01 UTC
    If you look at at the source you'll see FindBin first expands symlinks using readlink, and then runs the result through Cwd::abs_path which does the exact same thing. Brilliant isn't it?

    update: 

    sub File::Spec::dirname {
    my $self = shift;
    return $self->catpath( ( $self->splitpath(shift) )[ 0, 1 ] );
}
sub File::Spec::basename {
    my $self = shift;
    return $self->catpath( ( $self->splitpath(shift) )[ -1 ] );
}
sub File::Spec::realpath {
    my $self = shift;
    require Cwd;
    return $self->canonpath( Cwd::realpath(@_) );
}

    [download]

    MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
    I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
    ** The third rule of perl club is a statement of fact: pod is sexy.

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[d/l]
      You mean if I replace the while loop labelled with Resolve $script if it is a link just with ($RealScript,$RealBin) = fileparse($script); the module will still work? Please provide code to prove this.
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[d/l]
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Re^6: FindBin works differently on Fedora Core 2? (replace)
by eserte (Deacon) on Jun 08, 2004 at 16:29 UTC
    Once again we have an example of a feature that FindBin has but doesn't bother to export in a reusable manner (expanding symbolic links).

    FindBin does what it is made for. From the manpage:

    FindBin - Locate directory of original perl script
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[reply]
        I did. There is one answer by merlyn showing where the alternative will break (the chdir case), which makes it one to one in the number of bugs.

        Anyway, I was pointing out that the API of FindBin is correct (just supplying the paths of the directory containing the script), while the other poster insisted that it should make additional things (resolve symbolic links for arbitrary files).

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