difftime(3C)

difftime -- compute the difference between two calendar times

Synopsis

   #include <time.h>
   
   double difftime(time_t time1, time_t time0);

Description

difftime computes the difference between two calendar times. difftime returns the difference (time1-time0) expressed in seconds as a double. This function is provided because there are no general arithmetic properties defined for type time_t.

References

ctime(3C)