Is anyone familiar with ucontext?

This is a discussion on Is anyone familiar with ucontext? within the C++ Programming forums, part of the General Programming Boards category; I'm trying to use ucontext to create a thread library but I'm segfaulting. I'm using the debugger so I know ...

  1. #1
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    Is anyone familiar with ucontext?

    I'm trying to use ucontext to create a thread library but I'm segfaulting. I'm using the debugger so I know what the problem is but I don't really understand why. Using debugger I can see that the ucontext_ptr2 in Thread struct is always 0. The ucontext_ptr that I declared in the method however, does get a value but I just put that in as a test so when I call getContext it fails.

    Code:
    struct Thread
    {
    	char* stack;
    	ucontext_t* ucontext_ptr;
    	int heldLock;
    	int blockedLock;
    	int cv;
    };
    
    int thread_create(thread_startfunc_t func, void *arg)
    {
    	cout << "Creating Thread" << endl;
    	Thread* t = new Thread;
    	ucontext_t* ucontext_ptr2;
    	t->heldLock = -1;
    	t->blockedLock = -1;
    	t->cv = -1;
    	getcontext(t->ucontext_ptr);
    //////more code
    Last edited by jcafaro10; 02-01-2009 at 03:44 PM.

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    Compilers can produce warnings - make the compiler programmers happy: Use them!
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