http://unix.stackexchange.com/questions/167430/

tripleee@there:~$ procmail -m VERBOSE=yes /tmp/dot.procmailrc </dev/null
procmail: [4374] Wed Nov 12 19:34:22 2014
procmail: Rcfile: "/tmp/dot.procmailrc"
procmail: Assigning "MAILDIR=/home/tripleee"
procmail: Assigning "SHELL=/bin/sh"
procmail: Assigning "DEFAULT=/dev/null"
procmail: No match on "larry"
procmail: Assigning "LASTFOLDER=/dev/null"
procmail: Opening "/dev/null"
  Folder: /dev/null                                                           0

tripleee@there:~$ procmail -m VERBOSE=yes /tmp/dot.procmailrc <<HERE
> From: me
> To: larry
> Subject: so the To: header will match on the regex condition
>
> Here we go.
> HERE
procmail: [4386] Wed Nov 12 19:34:48 2014
procmail: Rcfile: "/tmp/dot.procmailrc"
procmail: Assigning "MAILDIR=/home/tripleee"
procmail: Assigning "SHELL=/bin/sh"
procmail: Assigning "DEFAULT=/dev/null"
procmail: Match on "larry"
procmail: Executing "sleep,10"
procmail: [4386] Wed Nov 12 19:34:58 2014
procmail: Match on "sleep 10"
procmail: Assigning "LASTFOLDER=/dev/null"
procmail: Opening "/dev/null"
 Subject: so the To: header will match on the regex condition
  Folder: /dev/null                                                          93

tripleee@there:~$ cat /tmp/dot.procmailrc
SHELL=/bin/sh
DEFAULT=/dev/null

:0
* larry
* ? sleep 10
{ }