c++ - I am getting a negative value when I try to convert a uint64_t to struct timeval? //edited - 


#include <iostream> #include <sys/time.h>  #include <stdint.h>  void convert(uint64_t offset ) {   struct timeval t;   t.tv_sec = offset / 1000000;   std::cout <<  "currenttimeoffset " << offset << "starttimeoffset " << t.tv_sec  << std::endl;   t.tv_usec =  offset % 1000000;   std::cout <<  "stattime usec " <<  t.tv_usec << std::endl ; }  int main(int argc , char** argv) {       uint64_t t = 18446744073709551615;   convert(t );   return 0; }

is there rounding error ? how accomplish ? routine called elsewhere code in convert. wrote small script example of uint64_t giving me negative number

offset / 1000000 produces value of 1.8446744073709551615 × 10^13 large tv_sec of type int32. max value can stored in int32 2.147483647 × 10^9.

you're overflowing integer you're storing result in, , wrapping around , becoming negative.


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