By default, procs that sleep usually expect their callers to wait for them to finish, so the callers must sleep as well. Using set waitfor=0 will disable that behavior, causing any sleep to return control to the caller immediately.
Example
mob/proc/LongLoop()
set waitfor = 0
while(1)
UpdateAI()
// proc will return to caller here
sleep(1)This setting will also dictate what happens if a callee sleeps. Consider an example where proc A calls proc B which calls proc C, and proc B has waitfor set to 0. When proc C sleeps, proc B will also sleep, but proc A will continue running as if proc B returned early. The . var currently in proc B will be used as its return value to A. When proc C wakes up and finishes, it will wake up proc B, but now B’s return value will be ignored since A is no longer waiting for it.
In older versions, the New proc always had waitfor set to 0 by default, but this was later changed. Now 1 is always the default, so setting waitfor to 1 will result in a warning that it is no longer necessary.