greetdelay is a program to introduce a small delay before an SMTP greeting. It also enforce RFC 2821's recommendation that SMTP clients not send any commands before receiving the greeting message.

If RELAYCLIENT is set in environment variable, greetdelay will be skipped. Set environment variable GREETDELAY to any numberic value greater than 0 to enable greetdelay to wait for the set value before executing other program.

If SMTP clients send any commands during the greet delay period, "554 smtp protocol violation (#5.5.1)" will be responsed with "premature input on stdin" will be printed in stderr and exit with exit code 111.

YOU ARE FREE TO USE THIS SCRIPT/PATCHES/GUIDE BUT I AM NOT RESPONSIBLE FOR ANY DAMAGE CAUSED! YOU HAVE BEEN WARNED!!!

08 Sep 2009 GMT +8 : Version 0.03

Fix the description

03 Sep 2009 GMT +8 : Version 0.02

Fix wait delay by checking the stdin first

02 Sep 2009 GMT +8 : Version 0.01

Initial release

» greetdelay.c

» gcc
» ucspi-tcp
» qmail

1. Download the source:

2. Compile:

3. Install:
4. In your smtpd run file, place greetdelay before qmail-smtpd (assuming greetdelay and qmail-smtpd is in your PATH):

5. Set environment variable GREETDELAY to any numberic value greater than 0 and export it in smtpd run file if you want to enable greetdelay globally or set it in your smtpd tcpserver rules.