- struct timeval _tv; \
- gettimeofday(&_tv, NULL); \
- fprintf(stderr, "%lu.%.6u:_trace()@%s:%u[%s]\n", _tv.tv_sec, _tv.tv_usec, __FILE__, __LINE__, __FUNCTION__); \
+ struct timeval _ctv; \
+ gettimeofday(&_ctv, NULL); \
+ if (!_itv) { \
+ _itv = true; \
+ _ltv = _ctv; \
+ } \
+ fprintf(stderr, "%lu.%.6u[%f]:_trace()@%s:%u[%s]\n", \
+ _ctv.tv_sec, _ctv.tv_usec, \
+ (_ctv.tv_sec - _ltv.tv_sec) + (_ctv.tv_usec - _ltv.tv_usec) / 1000000.0, \
+ __FILE__, __LINE__, __FUNCTION__\
+ ); \
+ _ltv = _ctv; \