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luckystarryesterday at 7:20 PM1 replyview on HN

I noticed back in the days that my FidoNet point client software ran a lot faster (actually processing a lot of messages, so IO and CPU heavy) in Windows than in DOS, which was unintuitive to me back then.


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mananaysiempreyesterday at 9:00 PM

Likely 32-bit file access[1] and the caching it included? The arrangement where Windows calls 16-bit MS-DOS entry points to do I/O (including from 32-bit programs) to respect preexisting DOS drivers, network redirectors, etc., but then in 3.11+ intercepts those 16-bit entry points (including when used from 16-bit DOS programs) to use a different 32-bit I/O stack when possible... it wasn’t intuitive back then and I don’t think it any more intuitive now.

[1] https://en.wikipedia.org/wiki/Microsoft_32-bit_file_access