FYI: The use of a fileshare and File::Copy are both incidental to the problem. The following one-liner demonstrates the memory growth under both 5.8.8 and 5.9.5.

The second one-liner also demonstrates that use Win32; definitely has the effect of slowing the growth rate:

## leaks rapidly. The sleep just avoids a fork bomb.
\as817\perl\bin\perl.exe -le"while(Win32::Sleep 10){$p=fork and waitpi
+d($p,0) or print(qq[kid:$$]),exit}"

## This leaks more slowly
\as817\perl\bin\perl.exe -mWin32 -le"while(Win32::Sleep 10){$p=fork an
+d waitpid($p,0) or print(qq[kid:$$]),exit}"
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