[SOLVED] <sys/time.h> gettimeofday conflict with Eth socket sendto
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<sys/time.h> gettimeofday conflict with Eth socket sendto
Whenever I enable gettimeofday in my code, previous working sendto(raw_eth, buffer, ...)
stopped working and
Error: Bad file descriptor.
Why is that?
the only thing I'm sure is it's not name pollution. Since all the variable defined in main() works if I make the wrap of gettimeofday an empty function.
In the absence of code the only explanation I can come up with is: wizards did it! If you don't wish to share the code of your program, write a different, smaller program which does little more but exemplify the problem you are facing; and post that program instead.
You're declaring a pointer to "struct timeval *" ... but your never ALLOCATING the timeval record that's being pointed to!!!!
Guaranteed segmentation violation
Just declare the variable, and pass "&addressof" into the function. It will make you much happier
PS:
Regrettably, a buffer overrun in one part of the program (e.g. your call time "gettimeofday()" with a bogus pointer) can (and usually will) cause a crash in a completely *different* part of the program (here, "sendto()". But just as easily "printf()", "malloc()" or just about any other standard library function).
BTW, what is the proper way of initializing the pointer of such struct if in some scenario I prefer to use pointer.
Simple - you declare the object (variable, struct, malloc() a block of memory - whatever) *first*. Then you can make as many or as few pointers as you want.
If you don't declare anything but a pointer ... well, then, it doesn't have anything to "point to", does it?
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