close_all_framegrabbers — Close all image acquisition devices.
close_all_framegrabbers( : : : )
The operator close_all_framegrabbers closes all currently open image acquisition devices. It is used to cope with deadlocks resulting from damaged image acquisition handles (in that case the use of close_framegrabber is impossible).
close_all_framegrabbers exists solely for the purpose of implementing the “reset program” functionality in HDevelop. close_all_framegrabbers must not be used in any application.
For a multithreaded application all image acquisition operators (as listed in open_framegrabber) are an own group in which info_framegrabber, open_framegrabber, close_framegrabber and close_all_framegrabbers are executed exclusively.
Thus, info_framegrabber, open_framegrabber, close_framegrabber and close_all_framegrabbers block the concurrent execution of all other operators within this group, but run in parallel with all non-exclusive operators outside of this group.
If it is possible to close all image acquisition devices, the operator close_all_framegrabbers returns the value 2 (H_MSG_TRUE). Otherwise an exception is raised.