Change the “From:” address in Unix “mail”

Question

Sending a message from the Unix command line using mail TO_ADDR results in an email from $USER@$HOSTNAME. Is there a way to change the \"From:\" ad

Answer 1

In my version of mail ( Debian linux 4.0 ) the following options work for controlling the source / reply addresses

• the -a switch, for additional headers to apply, supplying a From: header on the command line that will be appended to the outgoing mail header
• the $REPLYTO environment variable specifies a Reply-To: header

so the following sequence

export REPLYTO=cms-replies@example.com
mail -aFrom:cms-sends@example.com -s 'Testing'

The result, in my mail clients, is a mail from cms-sends@example.com, which any replies to will default to cms-replies@example.com

NB: Mac OS users: you don't have -a , but you do have $REPLYTO

NB(2): CentOS users, many commenters have added that you need to use -r not -a

NB(3): This answer is at least ten years old(1), please bear that in mind when you're coming in from Google.