Programmers with network engineering skills

William Herrin bill at
Mon Mar 12 17:01:38 CDT 2012

On Mon, Mar 12, 2012 at 5:32 PM, Owen DeLong <owen at> wrote:
> Whenever I've built code to check someone's email address on a form, I always just looked for the following:
> 1.      matches ^[^@]+@[A-Za-z0-0\-\.]+[A-Za-z]$
> 2.      The component to the right of the @ sign returns at least one A, AAAA, or MX record.

Hi Owen,

If I'm not mistaken, "B at M4N" is a legitimately formatted
email address which fails part one of your test. Something along the
lines of;bob at is also supposed to be
legit though it's been so long since I looked at it that I may have
munged the format.

No, I don't allow these in systems I've designed either. Just sayin'.

Bill Herrin

William D. Herrin ................ herrin at  bill at
3005 Crane Dr. ...................... Web: <>
Falls Church, VA 22042-3004

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