in reply to Re^2: get directory listing
in thread get directory listing

Yeah it's on one line and looks elegant. Unfortunately there is no error control and it skips directories with a leading '.' in the name (e.g. '.foo', '..bar').
  1. From perldoc File::Glob:
    The POSIX defined flags for bsd_glob() are: "GLOB_ERR" Force bsd_glob() to return an error when it encounters a directory it cannot open or read. Ordinarily bsd_glob() continues to find matches.
  2. Skipping directories with a leading dot may be a feature. One can glob '.*' if need be.
Not to say that there are not situations in which an explicit opendir & C. is actually preferrable. Indeed there are. My point being that in the vast majority of cases a simple glob would do instead. I think OTOH it has a stigma due to the fact that anciently it relied on a call to an external shell, which is what I read it in a book, but since I don't have effective experiennce with Perl 4, the last one that I think was set up like that, I cannot tell for sure...

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Re^4: get directory listing
by bluto (Curate) on Nov 08, 2005 at 19:35 UTC
    From perldoc File::Glob: ...

    Your one liner is no longer really one line if you go that way. For the OP's solution, you'll need to be able to construct some magic looking glob string with '*' and '.*', and you'll have to weed out '.' and '..' as well. Assuming you can do that easily, you'll have something like this...

    use File::Glob ':glob'; my @dirs = grep { -d } bsd_glob('/usr/darren/' . $some_magic_globstr_h +ere, GLOB_ERR); die "glob: $!" if GLOB_ERROR;
    ... which IMHO isn't shorter or easier to comprehend/maintain than this ...
    opendir my $dh, /usr/darren' or die "opendir: $!"; my @dirs = grep { -d } map { "/usr/darren/$_" } grep { !/^\.\.?$/ } re +addir $dh; closedir $dh or die "closedir: $dh"; # this line optional
    ... esp if you have to change what is matched in the future, but YMMV.
      Your one liner is no longer really one line if you go that way. For the OP's solution, you'll need to be able to construct some magic looking glob string with '*' and '.*', and you'll have to weed out '.' and '..' as well. Assuming you can do that easily, you'll have something like this...

      Fair enough! (++)

      However in my experience (but YMMV too!) I've found that in the vast majority of cases you either want:

      1. files after some definite name pattern in a given directory (e.g.: 'log--*'), or
      2. all files in a given directory hierarchy. In which case I usually resort to plain File::Find, although its "enhanced" cousins would do.

      Incidentally the "magic looking glob string" is nothing but '* .*'.