Email verification (was: [PHP] Removing Invalid Users)

"Steve Werby" <steve-lists@befriend.com> writes: > "Clayton Dukes" <cdukes@cdukes.com> wrote: > > How can I write code that will search the database and check the > > validity > of an email address, and if it's bad, to remove that > > entry from the database? > > Like Tom said, use regex to check the email is of a valid format. A small > percentage of servers can be contacted to find whether an email address is > valid, but fewer and fewer are allowing this so it's completely unreliable. There's a nifty little open source program called `vrfy' which does nice things about email veryfication. Finding it is left as an exercise to the interested (I found it in FreeBSD's ports). Excerpt from the man page: NAME vrfy - Verify electronic mail addresses SYNTAX vrfy [options] [-v] address [host] vrfy [options] [-v] -f [file] [host] vrfy [options] [-v] -p domain vrfy [options] [-v] -T domain [name] DESCRIPTION vrfy is a tool to verify electronic mail addresses. The only required parameter is the address to be verified. The actual verification will be carried out at the remote machine where mail to the given address would normally be delivered. This may be a mail exchange host and not the final destination host. If an explicit host is given as the second argument on the command line, the specified address is verified at that machine. The output of the program shows whether or not the address can be handled at the contacted host. Error messages will be printed if the address is invalid. If the address is recognized, the output shows the remote host's notion of the (possibly translated) address. If it represents a local user at that host, additional information about the user may be displayed. Note that if the address is accepted by the contacted host, but this is not the final destination host, one still cannot be sure that the address represents a valid recipient. It is a handy tool to verify local mail addresses. If you have set up a .forward file, you can verify your own address to check that the forwarding is done properly. If you specify an arbitrary name, you can check whether this resolves to any valid recipients. -- Arcady Genkin i=1; while 1, hilb(i); i=i+1; end