I've tested in more than one SO, and the problem is the same. Try to increase the number of threads, in order to increase concurrency and you will get the same result.

Here is one copy running 1000 concurrent threads: 

C:\test>junk4 -NTHREADS=1000
STOP: Tue May 19 16:26:26 2009
1000000 1242746771.5932.out

[download]

And this is 20 concurrent copies each running 100 concurrent threads each: 

C:\test>for /l %i in ( 1,1,20 ) do @start /b junk4 -NTHREADS=100
STOP: Tue May 19 16:07:35 2009
 100000 1242745650.6976.out
STOP: Tue May 19 16:07:35 2009
 100000 1242745651.0876.out
STOP: Tue May 19 16:07:36 2009
 100000 1242745651.15.out
STOP: Tue May 19 16:07:37 2009
 100000 1242745651.7896.out
STOP: Tue May 19 16:07:48 2009
STOP: Tue May 19 16:07:48 2009
STOP: Tue May 19 16:07:49 2009
STOP: Tue May 19 16:07:50 2009
STOP: Tue May 19 16:07:51 2009
STOP: Tue May 19 16:07:51 2009
STOP: Tue May 19 16:07:51 2009
STOP: Tue May 19 16:07:51 2009
STOP: Tue May 19 16:07:52 2009
STOP: Tue May 19 16:07:52 2009
STOP: Tue May 19 16:07:52 2009
STOP: Tue May 19 16:07:52 2009
 100000 1242745654.972.out
 100000 1242745654.8784.out
 100000 1242745656.0952.out
STOP: Tue May 19 16:07:52 2009
STOP: Tue May 19 16:07:52 2009
STOP: Tue May 19 16:07:52 2009
STOP: Tue May 19 16:07:52 2009
 100000 1242745656.142.out
 100000 1242745656.1576.out
 100000 1242745657.1092.out
 100000 1242745657.1716.out
 100000 1242745657.9048.out
 100000 1242745657.5304.out
 100000 1242745657.3432.out
 100000 1242745657.2652.out
 100000 1242745656.5476.out
 100000 1242745655.596.out
 100000 1242745655.8768.out
 100000 1242745654.7536.out
 100000 1242745654.3012.out

[download]

Nary a whiff of a problem. Still unconvinced it works fine here?

Is that other OS (I assume that's what you meant by SO?), based on the same kernel? Or compiled against the same CRT? Or both?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re^5: Threads: How to share a FileHandle to Write by BrowserUk
in thread Threads: How to share a FileHandle to Write by gulden

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