As mickeyn said, it is a precedence problem. With the hight precedence operator || you need an extra set of parentheses:
(my (undef,undef,$uid,$gid) = getpwnam(q[user1])) || die "oh no";
You asked "Should I start using or consistently?" IMO it is a good idea to do everything consistently, or to have a good reason for not doing so.

In reply to Re: || vs or by cdarke
in thread || vs or by andreas1234567

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