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From: annesville on 5 Feb 2007 06:41
Hello All,

I am still learning Perl. I am trying to write a script to
recursively list all the directories starting from a specified path.
Unfortunately it seems that the globbing function handles paths with/
without spaces in them very differently as shown by the test case
script below.

Some research seems seems to indicate that I would be better off using
opendir/readdir. Accepted, but I would like, as part of my learning
experience, for someone to explain in simple terms WHY the below
script handles different paths differently. Please note that I have
used literal paths, but in application I would obviously need to use a
variable - so if you suggest escaping the space, it is not so simple
(although it is do-able), and doesn't make any difference anyway.

I am using ActivePerl 5.8.8.820

Regards,
Nicolas

----- START PERL -----

use strict;
use warnings;

my $file;

print "--- Windows, unquoted ---\n"; # Returns a list of all files and
directories in 'C:\Windows'
foreach $file (<c:/windows/*>) {print "$file\n";};

print "--- Windows, quoted ---\n"; # Returns nothing
foreach $file (<"c:/windows/*">) {print "$file\n";};

print "--- Program Files, unquoted ---\n"; # Returns 'c:/program' as
the only result
foreach $file (<c:/program files/*>) {print "$file\n";};

print "--- Program Files, quoted ---\n"; # Returns a list of all the
files and directories in 'C:\Program Files'
foreach $file (<"c:/program files/*">) {print "$file\n";};

----- END PERL -----

From: Michele Dondi on 5 Feb 2007 09:36
On 5 Feb 2007 03:41:04 -0800, annesville(a)hotmail.com wrote:

>Hello All,
>
>I am still learning Perl. I am trying to write a script to
>recursively list all the directories starting from a specified path.
^^^^^^^^^^^
^^^^^^^^^^^

This calls for File::Find or some of its cousins, like
File::Find::Rule or File::Finder. If you insist on reinventing the
wheel, you may still look into them to see how they are implemented.

>Unfortunately it seems that the globbing function handles paths with/
>without spaces in them very differently as shown by the test case
>script below.

It's all duly explained in

perldoc File::Glob

: Since v5.6.0, Perl's CORE::glob() is implemented in terms of
: bsd_glob(). Note that they don't share the same
: prototype--CORE::glob() only accepts a single argument. Due to
: historical reasons, CORE::glob() will also split its argument on
: whitespace, treating it as multiple patterns, whereas bsd_glob()
: considers them as one pattern.

>Some research seems seems to indicate that I would be better off using
>opendir/readdir. Accepted, but I would like, as part of my learning

In some situations you prefer glob(), in some other opendir/readdir.
The latter is certainly more verbose, but in some cases it may be
needed if you want maximum flexibility.

>experience, for someone to explain in simple terms WHY the below
>script handles different paths differently. Please note that I have
>used literal paths, but in application I would obviously need to use a
>variable - so if you suggest escaping the space, it is not so simple
>(although it is do-able), and doesn't make any difference anyway.

See above.

>print "--- Windows, unquoted ---\n"; # Returns a list of all files and
>directories in 'C:\Windows'
>foreach $file (<c:/windows/*>) {print "$file\n";};

BTW: I would use angular parentheses like that all the time in
one-liners. But definitely *not* in any longer code.


HTH,
Michele
--
{$_=pack'B8'x25,unpack'A8'x32,$a^=sub{pop^pop}->(map substr
(($a||=join'',map--$|x$_,(unpack'w',unpack'u','G^<R<Y]*YB='
..'KYU;*EVH[.FHF2W+#"\Z*5TI/ER<Z`S(G.DZZ9OX0Z')=~/./g)x2,$_,
256),7,249);s/[^\w,]/ /g;$ \=/^J/?$/:"\r";print,redo}#JAPH,
From: annesville on 6 Feb 2007 01:36
Thanks for the pointers Michelle.

Nicolas

From: Michele Dondi on 6 Feb 2007 03:12
On 5 Feb 2007 22:36:22 -0800, annesville(a)hotmail.com wrote:

>Thanks for the pointers Michelle.

Not that I'm bothered or offended, but... Michele (italian masculine
name as opposed to Michelle, which is a french feminine one).


Michele
--
{$_=pack'B8'x25,unpack'A8'x32,$a^=sub{pop^pop}->(map substr
(($a||=join'',map--$|x$_,(unpack'w',unpack'u','G^<R<Y]*YB='
..'KYU;*EVH[.FHF2W+#"\Z*5TI/ER<Z`S(G.DZZ9OX0Z')=~/./g)x2,$_,
256),7,249);s/[^\w,]/ /g;$ \=/^J/?$/:"\r";print,redo}#JAPH,
From: annesville on 6 Feb 2007 09:13
On Feb 6, 10:12 am, Michele Dondi <bik.m...(a)tiscalinet.it> wrote:
> On 5 Feb 2007 22:36:22 -0800, annesvi...(a)hotmail.com wrote:
>
> >Thanks for the pointers Michelle.
>
> Not that I'm bothered or offended, but... Michele (italian masculine
> name as opposed to Michelle, which is a french feminine one).
>
> Michele
> --
> {$_=pack'B8'x25,unpack'A8'x32,$a^=sub{pop^pop}->(map substr
> (($a||=join'',map--$|x$_,(unpack'w',unpack'u','G^<R<Y]*YB='
> .'KYU;*EVH[.FHF2W+#"\Z*5TI/ER<Z`S(G.DZZ9OX0Z')=~/./g)x2,$_,
> 256),7,249);s/[^\w,]/ /g;$ \=/^J/?$/:"\r";print,redo}#JAPH,

Whoa! Sorry 'bout that. I obviously don't qualify as a citizen of the
global community yet!

BTW, I am sure there must be a shorter way to write your signiture :-)

Nicolas

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