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extract email adresses from some file (or any other pattern)

Terminal - extract email adresses from some file (or any other pattern)
grep -Eio '([[:alnum:]_.-]+@[[:alnum:]_.-]+?\.[[:alpha:].]{2,6})'
2009-11-22 21:14:49
User: fooBier
Functions: grep
extract email adresses from some file (or any other pattern)

Simply more email-adresses matched


There are 2 alternatives - vote for the best!

Terminal - Alternatives
grep -Eio '([[:alnum:]_.]+@[[:alnum:]_]+?\.[[:alpha:].]{2,6})' file.html
2009-06-16 20:19:47
User: wires
Functions: grep

find all email addresses in a file, printing each match. Addresses do not have to be alone on a line etc. For example you can grab them from HTML-formatted emails or CSV files, etc. Use a combination of


to filter them.

grep -aEio '([[:alnum:]_.-\+\-]+@[[:alnum:]_.-]+?\.[[:alpha:].]{2,6})'
2013-06-23 21:52:14
User: binarynomad
Functions: grep
Tags: grep email

This will catch most separators in the section of the email:

dot .

dash -

underscore _

plus + (added for gmail)

... and the basic dash '-' of host names.

grep -aEio '([[:alnum:]_.-]+@[[:alnum:]_.-]+?\.[[:alpha:].]{2,6})'
2013-05-30 07:17:32
User: nabil_kadimi
Functions: grep

The -a option in -aEio tells grep to treat binary files as text files.

Know a better way?

If you can do better, submit your command here.

What others think

People really should take the time to read RFC822 and RFC1035.

This regex is too limited in the username (e.g., plus signs are valid) and too permissive in the domain name (underscores are not valid).

To see how insane it is to try and create a single regex that correctly validates RFC822-compliant email addresses, here's one: http://www.ex-parrot.com/~pdw/Mail-RFC822-Address.html

I'd rather see a regex that was too permissive in the username and correct in the domain name. That way it's more likely to catch valid email addresses and bypass false positives.

Comment by KlfJoat 83 weeks and 4 days ago

Your point of view

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