Does the caster know when a spell with a variable duration ends?
I'm looking for a RAW answer (answers based on Pathfinder or D&D 3.0 are ok if there is no info on this in D&D 3.5); I haven't found one here, nor in the rules.
For example, time stop has a duration of 1d4+1 rounds.
- Does the character only know that he has between 2 and 5 rounds?
- Does he know exactly how long he has, since the spell affects himself (i.e. if he rolled a 1, he knows he has 2 rounds)?
What about color spray, since it is cast on another person?
If there is no such info, how should I handle this as a GM?