Brett_Tabke - 3:31 pm on Mar 2, 2013 (gmt 0)
I just tried this on my windows box and linux boxes and it always waits for the process to complete.
I think part of the issue is you maybe running an apache wrapper or other exec_cgi like module. These are pretty common among webhosts and panels. They limit things like forking processes and buffered output doesn't act as expected. (I've not dug to far into these as I have not had an issue).
Instead of 'long process' or even forking a process, I would use cron to process it. Write your 'long process' params to a file and have a cron job that runs every few minutes check for it and process it. (which is how email notifications are handled here)