[help]how to get the microsecond-precision in windows?

[wal_sug]

hello,
the windows API GetSystemTime() could return the current time by a SYSTEMTIME struct variable,then the windows API SystemTimeToFileTime could change this struct into the form of 100-nanoseconds that ever passed since since January 1, 1601 (UTC),this number is stored in a FILETIME struct which has a high part and a low part.
but now I wanna get the current seconds(like the time() in time.h) and the microseconds that within one second(this is the point),
How can I convert the 100-nanoseconds value to what I want?
Or is there annother effective way to do this?
thanks.
-yogo