a working Perl on xampp

Returning to both Windows and Perl after something of an absence.

The XAMPP application stack is a quick way to get a web server, database and scripting languages onto a Windows box (& other platforms as well). I seem to remember that it was one of the very first one-click application server installers back in the mid-2000s.

Anyway, the version of Perl bundled in the current release (1.8.1) is broken from the point of view of  adding new modules. There's a complex Google trail to be followed but the upshot is: it awaits fixing. It's perfectly usable as a script interpreter but when you try to add modules from CPAN it's missing required system libraries and tools.

The simplest solution is to install Strawberry Perl, which is a port of the language and it's supporting ecosystem to win32 or 64:

* install xampp
* install strawberry perl
* check your environment variables to ensure that strawberry's perl.exe is in the system path (by default: C:\strawberry\perl\bin - rather than inside C:\xampp somewhere).
* alter the shebang line of any cgi scripts you want to call on xampp's apache server to point at strawberry perl (by default at: C:\strawberry\perl\bin\perl.exe).

So your cgi scripts will still live in the location defined in xampp/apache (default: C:\xampp\cgi-bin)  but they will call the strawberry interpreter instead of the bundled one.

This way, your can use the standard CPAN method of adding Perl modules from the command line (perl -MCPAN -e shell) and it will compile and install them into a location where they can be found by strawberry Perl (C:\strawberry\perl\site\lib) - i.e. it's INC path.

sortable directories

Let's say that you have generated directories full of images from some app like Pure Data. This is pretty basic stuff but easy to forget.

Basically - files with names in a format like file001.jpg, file002.jpg...

In PD, simply provide an sprintf-style argument like: "/file/path/frame%03d.jpg" to the 'makefilename' object. Magic.

opendir DIR, $inPath or die "cannot access $inPath\n";
@imageFilenames = sort(grep{$_ ne '.' && $_ ne '..'} readdir DIR);
closedir DIR;

Without the sort function above, the order of filenames in @imageFilenames will be farily random. That's no good if you want to maybe run through a time series of image.

You may want to append the full path to each filename entry:

my ($i, $z) = (0,0);
foreach $z (@imageFilenames) {
$imageFilenames[$i] = join("", ($inPath, $z));
print "$imageFilenames[$i] \n";
$i++;
}

To shuffle this sorted array:

use List::Util 'shuffle'; # requires Perl 5.8 or later

my @shuffledFilenames = shuffle(@imageFilenames);

Or just omit the orginal sorting function perhaps.