[help] Program immplementing an alarm
Hi, I'm trying to implement an alarm in Haskell and wrote the following code: http://hpaste.org/7201 But it doesn't work as expected. The expected behaviour is: The user enters a time in minutes. If the time is reached, a bell rings. If, before the time is reached, he press enter, the program finish and prints the elapsed time. The actual behaviour is: The user enters a time in minutes. If time is reached, nothing happens. If the user press enter, the elapsed time is printed and the program finish. Also, if he pressed enter after the time had elapsed, the bell rings. Some ideas? Antonio Regidor García ______________________________________________ Enviado desde Correo Yahoo! La bandeja de entrada más inteligente.
Antonio Regidor García wrote:
I'm trying to implement an alarm in Haskell and wrote the following code: http://hpaste.org/7201 But it doesn't work as expected.
Hi, The getLine function ties up stdin. So the system function isn't able to proceed until getLine completes, even when it is in another thread. Try using System.Process.runInteractiveProcess instead of system. Don't forget to call waitForProcess on the process handle when you are finished, or you will be left with a zombie. Hope this helps, Yitz
Thanks! But, when trying to implement your solution, I recalled hWaitForInput and used it to implement the alarm. Anyway, thanks, probably I will need that for other programas. Antonio
The getLine function ties up stdin. So the system function isn't able to proceed until getLine completes, even when it is in another thread.
Try using System.Process.runInteractiveProcess instead of system. Don't forget to call waitForProcess on the process handle when you are finished, or you will be left with a zombie.
Hope this helps, Yitz
______________________________________________ Enviado desde Correo Yahoo! La bandeja de entrada más inteligente.
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Antonio Regidor García -
Yitzchak Gale