Hi Monks,

I've been using Mail::CheckUser for years, but today I noticed some inconsistent results.  Here are 2 examples (same 1 liner with different email address): 

$ echo "a@b.com" | perl -MMail::CheckUser=check_email,last_check -ne 'BEGIN{$Mail::CheckUser::Skip_SMTP_Checks = 1};chomp;for $i (0..9){print "$_ -> ";if (check_email($_)){print "OK\n"}else{print last_check()->{reason}."\n"}}'
a@b.com -> DNS failure: NXDOMAIN
a@b.com -> DNS failure: NXDOMAIN
a@b.com -> OK
a@b.com -> OK
a@b.com -> DNS failure: NXDOMAIN
a@b.com -> OK
a@b.com -> DNS failure: NXDOMAIN
a@b.com -> DNS failure: NXDOMAIN
a@b.com -> OK
a@b.com -> DNS failure: NXDOMAIN

$ echo "a@abczz123ffz.com" | perl -MMail::CheckUser=check_email,last_check -ne 'BEGIN{$Mail::CheckUser::Skip_SMTP_Checks = 1};chomp;for $i (0..9){print "$_ -> ";if (check_email($_)){print "OK\n"}else{print last_check()->{reason}."\n"}}'
a@abczz123ffz.com -> OK
a@abczz123ffz.com -> DNS failure: NXDOMAIN
a@abczz123ffz.com -> DNS failure: NXDOMAIN
a@abczz123ffz.com -> OK
a@abczz123ffz.com -> DNS failure: NXDOMAIN
a@abczz123ffz.com -> DNS failure: NXDOMAIN
a@abczz123ffz.com -> OK
a@abczz123ffz.com -> OK
a@abczz123ffz.com -> OK
a@abczz123ffz.com -> DNS failure: NXDOMAIN

$ perl -MMail::CheckUser -e 'print "$Mail::CheckUser::VERSION\n"'
1.21
Questions:
Q1. Do you get similar results?
Q2. Why am I getting inconsistent results?
Q3. Can you suggest a better way of doing this check? (Basically I want to at least check the syntax of the address and that the domain exists, and I want a result within a second.)

I'm running Perl v5.10.1 on Linux.

Thanks.
Tel2

In reply to Mail::CheckUser inconsistent results by tel2

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