2 library(process): Create processes and redirect I/O
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Availability::- use_module(library(process)).(can be autoloaded)
Source[det]process_wait(+PID, -Status)
[det]process_wait(+PID, -Status, +Options)
True if PID completed with Status. This call normally blocks until the process is finished. Options:
timeout(+Timeout)
Default: infinite. If this option is a number, the waits for a maximum of Timeout seconds and unifies Status with timeout if the process does not terminate within Timeout. In this case PID is not invalidated. On Unix systems only timeout 0 and infinite are supported. A 0-value can be used to poll the status of the process.
release(+Bool)
Do/do not release the process. We do not support this flag and a domain_error is raised if release(false) is provided.
Status is one of exit(Code) or killed(Signal), where Code and Signal are integers. If the timeout option is used Status is unified with timeout after the wait timed out.