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

I was just reading Beginners guide to File::Find in the Monastary Tutorials (and the pod documentation for File::Find) and was testing some of the examples.

The code is simple and is as follows:

#!/user/bin/perl

use File::Find;

find(\&print_name, ".");


exit(0);


sub print_name{
        print "[$File::Find::dir] [$File::Find::name]\n"
        unless(($_ eq ".") or ($_ eq ".."))
               }

[download]

The output is:

[.] 
[.] [./DAYS2MDH.M]
[.] [./INVJDAY.M]
[.] [./JDAY.M]
[.] [./mdy2doy.m]
[.] [./MyBigTest.pl]
[.] [./MyBigTest.vpd]
[.] [./MyLearn04.pl]

[download]

According to the Tutorial and the comments, this should work on a Win32 system (which is what I was testing this on). But rather than giving me the 'full path', it gives me '.'.

I seem to recall that on Win32 systems there can be problems with getting full path names; but the Tutorial says otherwise.

How does one get the 'full path' name rather than the '.'? Or just point me in the right direction to address this issue since I can't remember where I saw/read the caveats about path names re: Win32 system?

UPDATE: Thanks everyone. I went with the full directory approach in the find() and it works just fine. In scouting around CPAN I also found File::Find::Wanted which is a real nice, simple wrapper around File::Find and is a bit more intuitive than File::Find. Though it's not clear how one gets to the variables $File::Find::name, $File::Find::dir...which are really nifty in the File::Find module.

ack Albuquerque, NM

Replies are listed 'Best First'.
Re: How to Get Full Path Name on Win32 System
by FunkyMonk (Bishop) on Mar 11, 2008 at 21:26 UTC
    Either use the full path instead of ".", or use Cwd (current working directory) to find the full path of ".": 
    find(\&print_name, "c:/path/to/wherever");
#or
use Cwd;
find(\&print_name, cwd);

    [download]

[reply]
[d/l]
[select]

      Thanks, FunkyMonk. CWD works great with File::Find::find().

      ack Albuquerque, NM
[reply]
Re: How to Get Full Path Name on Win32 System
by bart (Canon) on Mar 11, 2008 at 23:05 UTC
    First of all, you should be careful when using File::Find mixing $File::Find::name with starting out from a relative path for the root directory: File::Find chdirs to the directory the file is in, for the callback, so the proper relative path there is in $_, not in $file::Find::name. Of course, it's a whole other ballgame when you start out from absolute paths.

    Anyway: use rel2abs as a class method from File::Spec, or as a function from File::Spec::Functions. Try: either of these: 

    use File::Find;
use File::Spec::Functions qw(rel2abs);

$\ = "\n";
find \&print_name, ".";

sub print_name{
    print rel2abs($_) 
      unless $_ eq "." or $_ eq "..";
}

    [download]
    or 
    use File::Find;
use File::Spec::Functions qw(rel2abs);

$\ = "\n";
find \&print_name, rel2abs(".");  
# or, just for ".": 
# use Cwd;
# find \&print_name, cwd;  

sub print_name{
    print $File::Find::name
      unless $_ eq "." or $_ eq "..";
}

    [download]

    There's a chance the formatting of the full path is still is not exactly the same as you expect from Windows: there could be a mixture of slashes or backslashes, or the case may not the same as the case for the real physical file/directory names. To fix both these issues, you can use GetLongPathName from Win32, which is a standard library on ActivePerl/Windows.

[reply]
[d/l]
[select]

      Thanks, bart. I just tried your first example and it worked just fine. Though I think I like the Cwd approach from FunkyMonk a little better.

      You wrote "...you should be careful when using File::Find mixing $File::Find::name with starting out from a relative path for the root directory: File::Find chdirs to the directory the file is in, for the callback, so the proper relative path there is in $_, not in $file::Find::name. Of course, it's a whole other ballgame when you start out from absolute paths."

      Good info. I appreciate it. I tried quite a variety of 'test cases' and all worked much better, as you note, with absolute paths than relative paths.

      You also noted that:

      "...There's a chance the formatting of the full path is still is not exactly the same as you expect from Windows: there could be a mixture of slashes or backslashes, or the case may not the same as the case for the real physical file/directory names. To fix both these issues, you can use GetLongPathName from Win32, which is a standard library on ActivePerl/Windows."

      There's a nice tutorial on just that point. It has a couple of nice Regex that can be used to go back and forth between the Win32 path separator and the Perl version (forward slash). I haven't tried the GetLongPathName from Win32, but I'll sure check it out. Again, thanks.

      ack Albuquerque, NM
[reply]
        GetLongPathName returns the case for the file paths as it is physically stored on disk — Windows path file names are case insensitive, but sometimes you want this exactly right.

        Note that there are also a few more related functions in that module, like for converting between long filenames (may contain spaces, can be longer than 8.3) and the 8.3 DOS compatible filenames.

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      Win32::GetLongPathName expanded the 8.3 form and fixed capitalization/case, but didn't standardize slash direction. I had to use Win32::GetLongPathName(abs_path $dirname) on both 'c:/docume~1' and 'C:\Documents and Settings' to get them to match.
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Re: How to Get Full Path Name on Win32 System
by Corion (Patriarch) on Mar 11, 2008 at 21:37 UTC
[reply]
[d/l]

      Looks interesting. I'll check it out. Thanks, Corion.

      ack Albuquerque, NM
[reply]
Re: How to Get Full Path Name on Win32 System
by Anonymous Monk on Mar 12, 2008 at 03:28 UTC
    File::Find pod says "complete" path ... vague
[reply]

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