A do-while loop is similar to a while loop, but the order in which the parts are executed is different.
Format
{
} while (condition);
Example
do
{
llSay(0, "monkey!");
} while (monkeysRemain());
This code will say “monkey!” once, and then continue saying “monkey!” as long as the function monkeysRemain() returns TRUE.
In a do-while loop, the statements are always executed at least once, then the condition is checked, and if it evaluates true, the statements are repeated.
A do-while loop is used to execute the statements one time, and then additional times. For a loop that executes statements only when a specific condition is true, see the while loop.
Finding a time to use this is rare. It’s a wrong solution when I use it (so the section ends up getting re-written). -BW
Accoding to Strife replacing a while loop with a do{}while wrapped in an if statement reduces bytecode size. -Chris
It also executes faster than a while loop, (the bytecode savings is 5 bytes) -BW aka Strife
Note: Because of the way LSL parser works (more details: http://w-hat.com/stackdepth), conditions in LSL are evaluated left to right, instead of right to left as in most programming languages. Check example on condition page.
Credit to: Lslwiki.net (not working) with changes made for brevity and clarity.