E-mail Signatures

Signatures, or .sigs as they are called, abound on the Internet. The purpose of this page is to provide information and utilities related to signatures.

I wrote this page primarily because I had written some scripts for random signatures to use with MUAs (esp. Pine), but since they didn't directly relate to my Pine pages, I thought I'd put them by themselves on a separate page.

Table of Contents

  1. What is a signature?
  2. What are sig-dashes?
  3. What is the McQ limit?
  4. Why is the McQ limit?
  5. What should go in a signature?
  6. When should a signature be taken out?
  7. Utilities
  8. Using fortune for signatures
  9. Links for further information

What is a signature?

A signature line is a small inclusion at the bottom of your e-mail messages. It's original purpose was to provide the name and e-mail address path of the sender, so that that information was available reliably even if the mail headers got garbled. Nowadays, message handling is standardized and mail transport is reliable, so it is no longer needed to serve that purpose.

Instead, people use signatures to add witticisms and propagate general profundity around the Internet.

Your signature is stored in a file, usually .signature in your home directory. MUAs read this file and add it to your outgoing messages.

If you want to use a signature in your messages, convention suggests two important considerations:

  1. You separate it from your message using sig-dashes
  2. It complies with the McQ limit

What are sig-dashes?

sig-dashes are a string of characters that separate your signature from the body of your message. This sequence is defined as the characters "-- " appearing on a line by themselves. (The quotes should be removed of course. Please note the space after the two dashes.)

This means that the sequence for sig-dashes is (newline)(dash)(dash)(space)(newline).

MUAs do many nifty things to signatures if they are thus separated from a message.


The McQ limit is named after George F. McQuary. He was a regular on the newsgroup alt.fan.warlord. The McQ limit is that the signature should be no larger than 80 columns wide and 4 lines long.

Why the limit?

Contrary to most people's belief, bandwidth is expensive. Sending large signatures wastes bandwidth. While the sender may not pay for it, there are countless many that will, including service providers, network access providers, line owners like the telephone companies etc. as well as the large number of people that pay for their Internet access by the kilobyte, or the time they stay connected.

It is unfair to burden these people with the cost of carrying what is generally useless information.

It becomes particularly important to limit your signature when posting to newsgroups and mailing lists when a large number of people will read your message, perhaps paying extra for reading your signature. It is also annoying to see several lines of a signature when one receives mailing lists in the digest format.

What should go in a signature?

Pedantically, your name and email address. However, people sometimes add additional contact information, URIs of their home pages, organizational information etc. You may of course add totally irrelevent information, quotes etc. as well, AS LONG AS IT SATISFIES McQ!

When should a signature be taken out?

Any time you reply to a message, trim the signature from the quoted text. The only signature that may appear in a reply message is your own. Quoted signatures waste even more bandwidth than the original ones.


This page's raison d'être. Unless otherwise stated, these scripts/programs were written by me. The ones that were written by me have sufficient documentation in their source. The others are their authors' business.

All of the scripts that were written by me that appear on this page are distributed under the GNU Public license. The text of the license is available at http://www.gnu.org/copyleft/gpl.html.

Using fortune for signatures

Probably the best way to get random signatures is to use the fortune program to generate them. To do this, you must first put all of your signatures into a fortune database.

Creating the fortune database

Write all of your signatures into one file like so:

My first signature goes here
My next signature goes here
Ad nauseum
My last signature goes here

Then, run strfile on this file. Assuming that I call the above file signatures, my command would be

$ strfile signatures

If strfile is not installed on your machine by default, there is a perl script that mimics it written by Theo Van Dinter. You can download it from his page at http://www.kluge.net/~felicity/ppt/strfile. I have a local copy here.

This will produce a file, signatures.dat which is the actual fortune database. You can now use the fortune program to generate random signatures from your collection.

Using fortune on the new database

The fortune program can use any fortune database to produce random epigrams. The documentation for the BSD version of fortune is available from the OpenBSD Manual Pages website. The entry for fortune is here.

If you don't have fortune installed on your computer, you can use a perl script from the Perl Power Tools collection. The fortune sources are here.

You can now tell your MUA to use the fortune program to use your fortune database to produce random signatures.

By default, this will not enforce the McQ limit, so it is up to you to use it responsibly. It should be easy enough to write a wrapper for fortune that will enforce it, but I'm too lazy now.