#ifndef BSD_SYS_TIME_TIMERSUB_H
#define BSD_SYS_TIME_TIMERSUB_H
#include <sys/time.h> /* struct timeval timersub */
#if !defined timersub
#define timersub(a, b, r) do { \
(r)->tv_sec = (a)->tv_sec - (b)->tv_sec; \
(r)->tv_usec = (a)->tv_usec - (b)->tv_usec; \
if ((r)->tv_usec < 0) { \
--(r)->tv_sec; \
(r)->tv_usec += 1000000; \
} \
} while (0)
#endif
#endif /* BSD_SYS_TIME_TIMERSUB_H */