condition_wait(+Handle, +Timeout)

Handle

A handle for an object supporting condition signaling

Timeout

Timeout in seconds (integer or float), or the atom 'block'

Description

This is a low-level primitive that, together with condition_signal/2 and with_mutex/2, can be used to implement synchronization between concurrent threads.

The predicate blocks the current thread's execution until condition_signal/2 on Handle is invoked by another thread.

See condition_signal/2 for usage pattern, examples, and a list of handle types that support this operation.

This predicate must always be executed in a context where the Handle has been locked, i.e. inside with_mutex/2.

NOTE: the predicate will also be unblocked (and succeed) when the engine receives a throw/exit request via engine_post/2.

Modes and Determinism

• condition_wait(+, +) is det

Exceptions

(4) instantiation fault

Handle or Timeout is not instantiated.

(5) type error

Handle is not a handle.

(5) type error

Timeout is neither integer, float, nor the atom 'block'

(6) out of range

Timeout is a negative number

(141) unimplemented functionality

Handle refers to an object that does not support this operation.

(170) system interface error

Operating system error, e.g. Handle was not locked.

Examples

See condition_signal/2

See Also