Howard Hinnant:
On Aug 22, 2007, at 11:55 AM, Howard Hinnant wrote:
Here's checked_condition:
After investigating the use cases for the "unchecked condition", I realized that my earlier checked_condition that I posted here wasn't quite right, at least if you considered it a debug tool. To this end I've rewritten it, and renamed it to condition_debug to emphasize its role. The previous version was allowing default constructed conditions to wait on different mutexes at the same time. This revised condition_debug allows default constructed conditions to only wait on different mutexes at different times. All simultaneous waits must be on the same mutex (even for a default constructed condition).
... The checks seem too strict. It's valid to notify_all and then rebind the condition to a different mutex, but your condition_debug will likely assert/throw as the awakened threads have not yet executed their postchecks. (Unless I'm overlooking something.) It's quite likely that only the implementor of pthread_cond_t may catch all errors in the general case. This does not diminish the utility of a checked condition that catches most errors in the typical case IMO.