Is there a way for my script to know which "mailing" system is on a server?

I've done this, 
    $mailprog = '/usr/sbin/sendmail';
    if (-d $mailprog) {
        # Installed
    } else {
        # not installed
    }

[download]
But that does not appear to be working. I know that it is installed, but it is not sending my mail which I do in the "Installed" place above.

Is there a different way? I am just giving this script to someone, whom I did not charge to build it, but I want to know who is using it and where. So it is sending me the server variables the first time it's ran, and only that time.

I would appreciate any tips or advice.

thx,
Richard

In reply to How to tell if a server has Sendmail? by powerhouse

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