title: Delete mails from send mail mailing queue
body: <p>I need to delete mails from my centos mailing queue.I'm using sendMail as MTA. I used the following command which I found by searching:
  cd /var/spool/mail
  rm -f *</p>
  
  <p>But nothing happened to my mailing queue.
  And one more thing that if I want to delete mails by subject wise.</p>