mail -a myfile.txt -t me@example.com -s "Here's my file"

mutt -a myfile.txt -s "Here's my file" -- me@example.com

mail -s "hello" RECEIVE@mail.com < /home/masoud/YOURFILE.txt

mail -s "hello" RECEIVE@mail.com -a /home/masoud/YOURFILE.txt

mail -s "hello" -a /home/masoud/YOURFILE.txt RECEIVE@mail.com

echo "your message here" | mail -s "title" -a /home/masoud/YOURFILE.txt RECEIVE@mail.com

mail -s "your subject" you@gmail.com -A /your/attachment/absolute/path < /home/you/message.txt

thunderbird -remote "xfeDoCommand(composeMessage,subject='S',to='you@example.com',body='B',attachment='/some/absolute/file.txt')"

thunderbird -remote "xfeDoCommand(composeMessage,subject='S',to='you@example.com',body='B',attachment='$(readlink -f file.txt)')"

thunderbird-compose () {
    thunderbird -remote "xfeDoCommand(composeMessage,subject='$1',to='$2',body='$3',attachment='$(readlink -f $4)')"
}

thunderbird-compose 'Some Subject' test@example.com 'Body of message' file1

mailx -a attachment.zip -s subject rctp@domain.to

echo "This is the message body" | mutt -a "/path/to/file.to.attach" -s "subject of message" -- recipient@domain.com