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Date: Fri, 19 Dec 2008 15:06:19 +1100
From: fred <zfred AT bigpond DOT com>
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Subject: gettimeofday - millisecond accuracy
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with my test of gettimeofday in cygwin it appears to be counting in 
milliseconds
rather than microseconds.

so I had a look at where it is coded, /winsup/cygwin/times.cc

...
gettimeofday (struct timeval *tv, void *tzvp)
{
  struct timezone *tz = (struct timezone *) tzvp;
  static bool tzflag;
  LONGLONG now = gtod.usecs ();
...

I notice there is
hires_ms NO_COPY gtod;


however lower down there is appears to be a hires_us
class coded.

So I am wondering what the story is behind this ?

I will look at testing some changes here and testing, just need to do a 
successful build from source
of as is first.....

I am looking for microsecond resolution, and see that hires_us is using 
QueryPerformanceFrequency/QueryPerformanceCounter,
so thats looking good I think?

I have code that does bitbanging to the parallel  port, it works 
perfectly under linux,  and would like
to see it work in cygwin also.

Thanks
 

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