Add this to the top of your code:

use Cwd;
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Then you can just:

$thisdir = cwd();
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This gets the directory the "safest" way. If you are definitely on unix, however, you can simply say:

$thisdir = `pwd`;
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which is usually what Cwd does on unix systems. It has a few other options, such as fastcwd() and getcwd() but they are not used much. You can grab the name of the script itself by looking in $0 or even __FILE__.

If you are doing it through the web, check out the environment variable 'SCRIPT_FILENAME'

$pwd = $ENV{'SCRIPT_FILENAME'};
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