The -d switch isn't working as I expected it to (test to see if its a directory)

heigold1 has asked for the wisdom of the Perl Monks concerning the following question:

Hi, I have some code where, i change to a certain directory, read the contents of the directory, and then do a foreach through the contents. I test if each member is a directory using the -d switch, however it seems to be recognizing all files AND direcories as only files. Could someone tell me if i'm using the -d switch properly? Response is greatly appreciated. Here is the code:

sub ScanDirectory{

    my ($startdir) = @_;
    chdir("$stardir\\") or die "Unable to enter dir $startdir:$!\n";

    opendir(DIR, "$startdir") or die "Unable to open $workdir:$!\n";

    my @names = readdir(DIR) or die "Unable to read $workdir:$!\n";

    closedir(DIR);

    foreach my $name (@names)
    {
        next if ($name eq ".");
        next if ($name eq "..");

        if (-d $name)      # is this a directory?
        {     
                print "DIRECTORY $currentDir \n";
        }
        else
        {
                  print "FILE $currentFile";
                # it always passes through this condition.
        }
}
[download]

Comment on The -d switch isn't working as I expected it to (test to see if its a directory) Download Code

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Re: The -d switch isn't working as I expected it to (test to see if its a directory) by Fletch (Bishop) on Jan 07, 2005 at 19:08 UTC
Same cause as is mentioned here Re: Getting file properties returns 1970 modify time. Addendum: Not everything that's a not-directory is a file (named pipe, socket, char or block device, et al depending on your OS) . . .	[reply]
Re: The -d switch isn't working as I expected it to (test to see if its a directory) by bluto (Curate) on Jan 07, 2005 at 20:29 UTC
If this is the actual code, then the problem is probably a typo ... `my ($startdir) = @_; chdir("$stardir\\") or die "Unable to enter dir $startdir:$!\n"; ^^^^^^^` [download] Since your chdir isn't going where you want, and the names don't have paths prepended to them, the '-d' test will fail. FWIW rather than chdir I usually just prepend the directory name to the paths. This is less error prone since you don't have to remember to chdir back to the previous directory.	[reply] [d/l]
Re^2: The -d switch isn't working as I expected it to (test to see if its a directory) by sgifford (Prior) on Jan 07, 2005 at 21:40 UTC
Using `chdir` is about twice as fast: `$ perl chdir_benchmar Benchmark: timing 1000 iterations of with_chdir, without_chdir... with_chdir: 16 wallclock secs ( 8.11 usr + 8.46 sys = 16.57 CPU) @ 60.35/s (n=1000) without_chdir: 31 wallclock secs (10.98 usr + 19.15 sys = 30.13 CPU) @ 33.19/s (n=1000)` [download] Read more... (852 Bytes)	[reply] [d/l] [select]
Re^3: The -d switch isn't working as I expected it to (test to see if its a directory) by bluto (Curate) on Jan 07, 2005 at 23:08 UTC
Not on my mac G5 with a directory of 10,000 files... `Benchmark: timing 100 iterations of with_chdir, without_chdir... with_chdir: 25 wallclock secs ( 3.02 usr + 20.31 sys = 23.33 CPU) @ 4 +.29/s (n=100) without_chdir: 28 wallclock secs ( 3.76 usr + 21.65 sys = 25.41 CPU) @ + 3.94/s (n=100)` [download]	[reply] [d/l]
Re^4: The -d switch isn't working as I expected it to (test to see if its a directory) by sgifford (Prior) on Jan 07, 2005 at 23:55 UTC
Re^5: The -d switch isn't working as I expected it to (test to see if its a directory) by bluto (Curate) on Jan 10, 2005 at 16:37 UTC
Re: The -d switch isn't working as I expected it to (test to see if its a directory) by amw1 (Friar) on Jan 07, 2005 at 19:27 UTC
This slug will do what you want as well. `use strict; use File::Find; my $startdir = "/some/directory"; sub wanted { return if ($File::Find::name eq "." \|\| $File::Find::name eq ".."); if(-d $File::Find::name) { print "DIRECTORY " . $File::Find::name , "\n"; } elsif(-f $File::Find::name) { print "FILE " . $File::Find::name . "\n"; } else { print "OTHER " . $File::Find::name . "\n"; } } File::Find::find({wanted => \&wanted}, $startdir);` [download] there are shorter ways to write this but the basic idea is the same. find2perl is often useful to get a starting point for these as well.	[reply] [d/l]