renaming subdirectories on MS Windows

momo33 has asked for the wisdom of the Perl Monks concerning the following question:

Hello Monks, I want to rename subdirectories based on the content of some files in that directory. On GNU/Linux I have it working, but MS Windows fails: no rename is done. The depth of the tree is arbitrary, but the name of the directory containing the file needs to be changed. There are no directories in the directory that needs a name-change. Can anyone help? The failing code (cut to the bare essentials):

#!/usr/bin/perl
use File::Find;
use File::Copy;

sub FindData {
    my $fulldir  = $File::Find::dir;
    my $filename = $File::Find::name;
        ...
        open( IN, "<$filename" ) || die "cannot find $filename \n";
        ....
        close IN;
        if ($olddir ne $newname) {
        move( "$basedir/$olddir", "$basedir/$newname" );
        }
    }
}

finddepth( {wanted=>\&FindData,no_chdir}, @path );
[download]

Thank you very much

Comment on renaming subdirectories on MS Windows Download Code

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Re: renaming subdirectories on MS Windows by roboticus (Chancellor) on Nov 03, 2010 at 20:41 UTC
momo33: You'll probably have to cache the renames, and do them after you've traversed the directory tree since Windows isn't going to want to let you rename a directory when a process is using it. Something like this: `my @renames; ... sub wanted { ... push @renames, [ $old_name, $new_name ]; ... } ... find(...); for (@renames) { move $$_[0], $$_[1]; }` [download] You may be able to do it using the `no_chdir` option on File::Find, but I don't know. (File::Find may have the directory open anyway as part of how it works.) ...roboticus Update: Fixed missing code tag.	[reply] [d/l] [select]
Re^2: renaming subdirectories on MS Windows by momo33 (Beadle) on Nov 03, 2010 at 21:02 UTC
This seems to work: thank you!	[reply]
Re: renaming subdirectories on MS Windows by toolic (Bishop) on Nov 03, 2010 at 20:45 UTC
You can get more information as to why the move failed by checking its RETURN value: `move( "$basedir/$olddir", "$basedir/$newname" ) or die $!;` [download] Another piece of generic advice: use strict and warnings	[reply] [d/l]
Re: renaming subdirectories on MS Windows by Jim (Curate) on Nov 04, 2010 at 00:00 UTC
You won't be able to rename subdirectories on Microsoft Windows using Perl, at least not easily, portably, correctly and without a lot of arcane folderol using Win32 modules. Perl can't handle folder and file names with any characters in them outside the Basic Latin and Latin 1 Supplement blocks of Unicode. See Is File::Find Unicode-(Conformant\|Compliant\|Enabled\|Capable)? and dos path accents.	[reply]
Re: renaming subdirectories on MS Windows by Anonymous Monk on Nov 03, 2010 at 21:07 UTC
I've written dozens of these scripts, and am very leery of doing actual renaming in program. I much prefer to generate a shell script to do my renaming, so that I can review it before any actual renaming is done `mv "one" "two"` [download] This also avoids the problem you're experiencing on win32, trying to rename a directory while its in use	[reply] [d/l]
Re^2: renaming subdirectories on MS Windows by aquarium (Curate) on Nov 03, 2010 at 22:01 UTC
that's exactly what i would do. write a perl or whatever script to figure out which directories to rename, and the script generates a shell/batch file of the rename commands. you can review this batch rename commands before actual execution. the directory paths will need to be appropriately quoted to avoid problems. the hardest line to type correctly is: stty erase ^H	[reply]
Re: renaming subdirectories on MS Windows by locked_user sundialsvc4 (Abbot) on Nov 04, 2010 at 13:01 UTC
Windows’ directory-traversal routines have never played well with code that manipulates the files or directories in any way. No matter what language you are using, cache the names first, then troll through the list you’ve built. This is true no matter what language you’re using, and as far as I know, it has been this way since Windows 3.1 if not earlier.
Re^2: renaming subdirectories on MS Windows by Jim (Curate) on Nov 06, 2010 at 04:37 UTC
No matter what language you are using, cache the names first, then troll through the list you’ve built. But you can't do this with Perl. Perl can't read Unicode file names on Windows. In general, Perl can't be used to work with folders and files on a Windows files system, even just to read their names, at least not simply and reliably.	[reply]