rolldice [ options ] dice_string dice_string ...


rolldice rolls virtual dice. The dice strings passed on the command line contain information on the dice to roll in a format comparable to the format used in fantasy role playing games.



returns the usage of diceroll


returns the version of diceroll


uses /dev/random for random number generating


uses /dev/urandom for random number generating (default)


prints out the result of each individual die separately, as well as the operations and totals


The dice string uses the following format:


The dice string doesn't have to be in the format that I outlined above, but this is the nicest order for me. It will try to parse any different string containing the same sections in the best way it can, and will throw out anything that isn't one of the sections below.


This is the only required part of the string, and now really isn't even required, as it defaults to 1d6 if not found. The first number is the number of dice to roll, and the second number is the number of sides the dice have. The numbers rolled on each die are then added up and given as the result. Hence 3d6 means "roll three six-sided dice, add them together and return the result". If the first number is left out, then the number of dice defaults to 1. If the second number is not a number, but a percentage sign, then the number of sides becomes 100 (for a percentage roll).


This number tells how many times to roll. For example, if you want to roll 3 6-sided dice 6 times, you would say 6x3d6. This would return six numbers, corresponding to the six different rolls.


This number tells how many times to multiply the result of each roll. 3d6*100 would return a number in the range of 300-1800, since 3-18 is the range resulting from 3d6, which is then multipled by 100.


This number is the modifier to be added or subtracted, depending on the sign, from each roll. 1d4+1 would result in a range from 2-5 (1-4 for the die, plus 1). This step is handled *after* the multiplication modifier.


This number tells the program to drop the # lowest dice rolls. This step is handled *before* the multiplication modifier.

in the order show above. For an extreme example, "3x4d6*5+1s2" would roll four six-sided dice, drop the lowest two, multiply the result by 5, add 1 to that, and repeat the process two more times, for a total of three results.


The following error messages may appear on STDERR:

Failure in getting dice attributes

Either memory could not be allocated while parsing the string passed to the rolldice program or an invalid dice string was entered.

Failure in rolling dice

Memory could not be allocated while actually rolling the dice.

Unknown option

Take a wild guess ;)


I haven't noticed any yet... rolldice is a quick hack to provide a virtual dice roller for FRPGs that I play. Any improvements are greatly welcome, as I am not the most experienced C coder...


Stevie Strickland <[email protected]>


1.10 - 25 Nov 2001