[Haskell-beginners] forkProcess behaviour

[PICCA Frederic-Emmanuel]

Hello,

I try to write a service which execute an IO using forkProcess
This service contain a web server whcih avwait for job published by users.
for each job, I create a forkProcess of this job. I need to fork the process in order to change the uid and gid of the process for each of the job dependencing on who request the job.

I have a least two questions

1) is this forkProcess a fork of all the current process, or is it just an executin of the IO in another process id ?

I ask this because sometime one of my job hang and a process keep running. Since the original process is binded to a port, it is not possible to restart the server, saying that the port is already in use.

2 ) How can I catch the exceptions thrown from the child process in order to process them in the parent process.

thanks for your help answering these questions.


Frederic