Error writing files of exact size 0xffffffff on Windows

[Siskin-Bot]

Submitted by: Hostilefork

The GetFileSize API returns two DWORDs worth of size, for the low and high 32-bits of the file's actual 64-bit size. For some reason, errors are indicated by returning a low size of 0xffffffff and using SetLastError() to something other than NO_ERROR. But if the last error is NO_ERROR, that means the file really is 0xffffffff bytes long.

R3-Alpha doesn't check the error condition, hence it conflates errors with a legitimate size for a file to have (especially if it is growing incrementally bytes by bytes, to pass through such a size at some point).

https://github.com/rebol/rebol/blob/25033f897b2bd466068d7663563cd3ff64740b94/src/os/win32/dev-file.c#L348

(Pointing it out as a curiosity of API design more than anything. Issue is resolved in Ren-C by checking the error status, and if it is NO_ERROR then not reporting an error.)

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^{Imported from: metaeducation#2282}

Comments:

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Hostilefork added the Ren.resolved on Nov 28, 2017

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