Hello
I have background scripts using zsystem flock. After a few hours OS X is out of descriptors. Turns out system.c doesn't close descriptor initially opened and passed to movefd(), when lock doesn't succeed. The patch adds preceding zclose(flock_fd) to all return 1 and return 2 code paths.

Just to mention, I might still resolve the script issues by changing code to use subshell closed on unsuccessful lock, unsure yet.

-- 
Sebastian Gniazdowski
psprint /at/ zdharma.org