[Haskell-cafe] When is waitForProcess not necessary?
Brandon S. Allbery KF8NH
allbery at ece.cmu.edu
Thu Aug 2 23:57:51 EDT 2007
On Aug 2, 2007, at 23:52 , Dave Bayer wrote:
> If one is calling runInteractiveCommand for a "sure-thing"
> returning a small
> amount of output (say, "ls" for a modest directory"), is it
> necessary to call
> waitForProcess?
Most operating systems only let you have a small number of
outstanding child processes; once you hit it, you'll need to wait()
(aka waitForProcess) to reap the dead children before you can launch
any more.
If you're only doing it once, you can ignore waitForProcess and let
the OS's process exit stuff reap the child for you --- but I suggest
documenting that you've done this, in case you later change the
program to run more children and they start failing with "Too many
processes".
--
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university KF8NH
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