Change the "From:" address in Unix "mail"

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.commail -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.

On Centos 5.3 I'm able to do:

mail -s "Subject" user@address.com -- -f from@address.com < body

The double dash stops mail from parsing the -f argument and passes it along to sendmail itself.

GNU mailutils's 'mail' command doesn't let you do this (easily at least). But If you install 'heirloom-mailx', its mail command (mailx) has the '-r' option to override the default '$USER@$HOSTNAME' from field.

echo "Hello there" | mail -s "testing" -r sender@company.com recipient@company.com

Works for 'mailx' but not 'mail'.

$ ls -l /usr/bin/maillrwxrwxrwx 1 root root 22 2010-12-23 08:33 /usr/bin/mail -> /etc/alternatives/mail$ ls -l /etc/alternatives/maillrwxrwxrwx 1 root root 23 2010-12-23 08:33 /etc/alternatives/mail -> /usr/bin/heirloom-mailx