You're confusing the concepts of "defined" versus "false", which are very different in Perl. The getpwnam document mentions

If the entry doesn't exist you get the undefined value.
Thus, you need a test as mirod has outlined above.

The same consideration applies anytime a value that represents falsehood in Perl (0 or the empty string) can be a legitimate return result from a function. One of my favorite Perl books, Effective Perl Programming has an excellent section on the difference.

In reply to Re: UID 0 and getpwnam by VSarkiss
in thread UID 0 and getpwnam by c

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