The reason that works is because there is no child process involved.

The called script is processed by the calling process--in the same fashion as Perl's do script.pl;--and the changes are made to the current process' environment by the current process.

The effect is exactly the same as: 

## Called .pl
$::ENV{ somekey } = 'somevalue';

##calling script;
do 'called.pl';

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In reply to Re^4: Can I do this ??? by BrowserUk
in thread Can I do this ??? by Anonymous Monk

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