Question

How does one get the current user in a portable way?

This seems like an FAQ but perlport doesn’t speak about it, maybe because some odd systems don’t have the concept of “user” to being with? However, let’s stick to *nix and Windows.

getpwuid($>) is not implemented on Windows.

$ENV{USER} || $ENV{USERNAME} seems finicky.

http://search.cpan.org didn’t turn up much.

Answer 1

getlogin:

This implements the C library function of the same name, which on most systems returns the current login from /etc/utmp, if any. If null, use "getpwuid".

$login = getlogin || getpwuid($<) || "Kilroy";

Do not consider "getlogin" for authentication: it is not as secure as "getpwuid".

You can also try ||-ing this with POSIX::cuserid() and Win32::LoginName().