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8186 :: Pragma to restrict procedure to main thread?

• mildred (orginal) [2021-07-02T22:28:35+02:00] view original

  Hello,

  I was wondering if there was a pragma to restrict the use of some procedures to the main thread.

  The use case I have is that I did some bindings of the glibc DNS resolution procedures in the resolv nimble, and I believe that the glibc procedures are not thread safe. As such, I would like to restrict the nim procedures to a single thread only.

  There is the {.gcsafe.} pragma that kind of does the opposite, but it's tied to the garbage collector that's going away. And I want to specifically mark a procedure not thread safe.

  Perhaps if that does not exists, it could be a nice small addition.

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• Araq (orginal) [2021-07-03T06:48:37+02:00] view original

  You can use code like this:

  var mainThread = getThreadId()
  
  proc foobar =
    ## This needs to be called by the main thread:
    assert getThreadId() == mainThread
  
  Run

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• mildred (orginal) [2021-07-03T10:22:55+02:00] view original

  Thank you, I was more expecting a compile time pragma, but that would do. Just a question, I could not find mainThread in the library documentation. Where can I find it? Thank you

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• Araq (orginal) [2021-07-03T12:05:50+02:00] view original

  It's declared in the first line of my snippet.

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