More detail would be helpful, but sounds like an infinite (Async?) thread. Try

    bracket (newStablePtr a) freeStablePtr (const $ wait a)

+google to find out why.

2015-02-04 13:59 GMT+01:00 Magicloud Magiclouds <magicloud.magiclouds@gmail.com>:

Hi,

  I met an issue while I was using xhb. When a certain property of root window being changed, it was supposed to give me an AccessError. But actually I got "thread blocked indefinitely in an STM transaction" when I waitForEvent.

  AFAIK, in xhb, it forks a thread to read what X server sends. Then parse and put it into a TChan. waitForEvent reads from the TChan.

  It is reasonable to me that if X server did not send anything, then waitForEvent would be blocked. But apparently there are some other policies in RTS.

  So what is that? And how should I debug it?

--

竹密岂妨流水过
山高哪阻野云飞

And for G+, please use magiclouds#gmail.com.

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