The shell doesn't do any writing here. It merely redirects STDOUT to point to the file and then fork/execs the new process. Backticks won't do anything more than system() here either -- it won't ensure you get all of the output. If the system'd process forks itself into the background, backticks (like system) will return immediately and stop grabbing output at that point.

You need to find out which process is not waiting (lwp-request?) and either stop it from doing that or reimplement that part only in perl. (gbarr's suggestion to check for '&' is a good start.)

bluto