Brandon S. Allbery KF8NH wrote:
On Jun 24, 2009, at 02:27 , Sittampalam, Ganesh wrote:
Brandon S. Allbery KF8NH wrote:
Sure - but it hurts more when in some environments you get away with it and others you don't.
You'll still have that though, it'll just be a different set of environments. The next failure mode after this one is writing more than _PIPE_BUF down ih; you'll deadlock in the write when in blocking mode, in non-blocking mode it depends on how the runtime handles partial writes.
I'd hope for consistency across the GHC runtimes though.
You can hope, but I get the impression blocking/non-blocking maps to threaded/non-threaded respectively in which case all bets are off. (Unless the ghc runtime guarantees some specific behavior here.)
I believe that from the point of view of each Haskell thread, the IO will always be blocking (unless you explicitly used a non-blocking call), but the GHC runtime actually handles the IO using select and non-blocking calls, and so avoids blocking the entire program, and that this doesn't vary between the threaded and non-threaded runtimes. That's why I found it confusing that a program that just did IO could behave differently on the two runtimes, until I found the bug in it. Ideally, the program would have deadlocked on both runtimes. Ganesh =============================================================================== Please access the attached hyperlink for an important electronic communications disclaimer: http://www.credit-suisse.com/legal/en/disclaimer_email_ib.html ===============================================================================