Re: the first set of questions:

1a. perl -M[MODULE NAME] -e '1' will die with an error message.
1b. IIRC, IO::File and members of its clan are standard with recent versions of Perl (v. >= 5.00503?)

2. You can open a file for writing by passing "> [filename]" to the constructor. You then pass the object thus created around.

3. The fine manual is for reading ... but the overall best way is to configure the CPAN module and it will do most things for you automagically, i.e. once it's configured, a simple perl -MCPAN -e 'install [MODULE NAME]' will suffice for most modules.

Philosophy can be made out of anything. Or less -- Jerry A. Fodor