How do you invoke and send mail from unix ?

This is how you can do mailx from the unix prompt.
Go to the path where the source file resides.
pwd> uuencode | mailx

usually in big corporations your network id is mapped to your email address.

The following is a more detailed example for using mailx in shell script. This should help.

Code
SUBJECT="Email Subject Line"
TO=xyz@company.com
CC=`tr '
' ', ' < mailCClist.txt`
#BCC="xyz2@comp.com"
 
echo "Send the E-mail message..."
/usr/bin/mailx -s "${SUBJECT}" ${TO} <<-END
 
~< ! uuencode $DCdir/$FileName "Result.txt"
 
~c ${CC}
~b ${BCC}
        Hi,
 
        Blah, Blah.. body of the email.
 
        Thanks
        Satya
        ~.
        END
 
echo "Mail Sent!!"
 

Code
mailx -s "<subject>" <email_id list> < <input_file>