Command line app that verifies email(s) address existence
As simple as that: ./mailvalidator -h
Name: mailvalidator v.1.0.1
Description: The mailvalidator utility perfoms email address validation tests such as MX servers existence and 250 SMTP reply code. Email(es) for validation can be provided in the form of a single argument or a plain-text file containing list of emails. Nameservers from etc/resolv.conf are used or 8.8.8.8 by default.
Usage: mailvalidator [@server] [-h] [-l] [-a] [-f filename] [-fsize filesize] [-xlist filename] [-d delay msec.] [-t socket timeout sec.] [-mx mail servers number] [-p ptr record] [-s mailfrom] [rcptto]
Options: -h Output this help screen. @server IP address of the name server to query, if not stated and resolve.conf is unusable, then 8.8.8.8 to be used by default. -a Perform FQDN A record test (please note, FQDN without A record can still have MX records), default OFF. -d NUM Delay in msec. to be set while processing a list of emails, default 100. -flist filename File name containing a list of emails. -fsize NUM Lines (i.e. emails) number limit to be used in file mode, default 500. -l Enable logging, default OFF. -mx NUM MX servers number to be attempted, default 3. -p ptr record PTR record to be used for EHLO command, default educause.edu. -s mailfrom MAIL FROM to be used while checking 250 SMTP reply code, default admin@educause.edu. -t NUM Socket timeout in sec. to be set while establishing connectivity, default 15. -xlist filename Filename containig blacklisted domains, to be used excluded from validation.
Arguments: rcptto Email address to be verified.