timeval DESCRIPTION The functions gettimeofday and settimeofday can get and set the time as well as a timezone. The tv argument is a timeval struct, as specified in <sys/time.h>: struct timeval { time_t tv_sec; /* seconds */ suseconds_t tv_usec; /* microseconds */ }; 其中返回的timeval值为Epoch（00:00:00 1970-01-01 UTC）到创建struct timeval时的时间，tv_sec为秒数部分，tv_usec为微秒数部分（10的-6次方秒）。比如当前程序运行的tv_sec为1244770435，tv_usec为442388，即当前时间距Epoch时间1244770435秒，442388微秒。测试代码如下： #include
