buildFdSets: file descriptor out of range

[Kazu Yamamoto ( 山本和彦 )]

Hello,

If this is not a right place to ask this question, please tell me
another place to ask.

I'm developing a mail server with GHC 6.10.3 on Linux. The server is
running well at the beginning. But after several hours, it receives an
error, "buildFdSets: file descriptor out of range".

Please tell me what happened? And please suggest me how to fix this
problem.

Here is brief description of the server.

- linked with ADNS.
- complied with the -threaded option since ADNS requires it.
- uses forkIO to produce threads.
- does not use "deamonize" of System.Posix.Daemonize since it uses
  forkProcess. I execute my server as foreground process.
- Because there are so many nasty SMTP clients, most SMTP
  connections are time out. Handles of the SMTP connections
  disappear, so I cannot use "hClose" to close the handles.
- pushes the limit of file descriptors to 65536 with setResourceLimit.

--Kazu