Passing pointer to struct through mailslots, memory allocation?

This is a discussion on Passing pointer to struct through mailslots, memory allocation? within the C Programming forums, part of the General Programming Boards category; I'm using mailslots to pass structs between programs, or more precisely pointers to those structs. It is "working" as its ...

  1. #1
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    Passing pointer to struct through mailslots, memory allocation?

    I'm using mailslots to pass structs between programs, or more precisely pointers to those structs. It is "working" as its passing something, but I'm unable to print out anything from the structs on the receiving program. Do I have to do anything with memory allocation or am I missing something else?

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    and the hat of wrongness Salem's Avatar
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    Each program has a separate virtual address space.
    So a pointer to data in one program is meaningless to any other program.

    You need to pass actual data.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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    How do I accomplish this when WriteFile wants a pointer?

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    and the Hat of Guessing tabstop's Avatar
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    Is this different than any other time you write out data? If you had
    Code:
    char big_pile_of_data[1024];
    how would you use WriteFile to any file?

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    I think WriteFile would handle that big_pile_of_data just fine.

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    Worked around it, just sent all the data separately.

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