[Haskell-cafe] haskell and releasing resources

Fawzi Mohamed fmohamed at mac.com
Wed Feb 7 04:32:22 EST 2007

On Feb 7, 2007, at 1:05 AM, Donald Bruce Stewart wrote:

> mail:
>> Hi,
>> Am Dienstag, den 06.02.2007, 15:56 +0100 schrieb Fawzi Mohamed:
>>> I am replying to myself, but anyway with it seems (from the
>>> documentation) that
>>>      forkIO (do{ waitForProcess pid; return () })
>>> is the best solution, and does not seem to lead to wasted resources.
>> This does not work for me. According to strace, the spawned  
>> process is
>> in a blocking write, the haskell process is in a blocking waitpid,  
>> and I
>> am sure that the program would consume all output.
> Any difference with -threaded ?

strange for me it works beautifully, even without -threaded, maybe  
your process writes to stderr?
you could do something like

     forkIO (do{ length(hGetContents err); return () })

(not  tested) if you are not interested to the error output (and  
maybe also a length of the input to be sure that you have read it all...


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