FAQ 9.19 How do I return the user's mail address?

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This is an excerpt from the latest version perlfaq9.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at http://faq.perl.org .


9.19: How do I return the user's mail address?

    On systems that support getpwuid, the $< variable, and the Sys::Hostname
    module (which is part of the standard perl distribution), you can
    probably try using something like this:

        use Sys::Hostname;
        $address = sprintf('%s@%s', scalar getpwuid($<), hostname);

    Company policies on mail address can mean that this generates addresses
    that the company's mail system will not accept, so you should ask for
    users' mail addresses when this matters. Furthermore, not all systems on
    which Perl runs are so forthcoming with this information as is Unix.

    The Mail::Util module from CPAN (part of the MailTools package) provides
    a mailaddress() function that tries to guess the mail address of the
    user. It makes a more intelligent guess than the code above, using
    information given when the module was installed, but it could still be
    incorrect. Again, the best way is often just to ask the user.


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