Microsoft Just Released MS-DOS Source Code!
Microsoft Just Released MS-DOS Source Code!
The original sources of MS-DOS 1.25, 2.0, and 4.0 for reference purposes - microsoft/MS-DOS
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Who the hell writes stuff like this in asm, honestly? Hasn't C been around since like the 70s
"Who the hell" writes an OS in assembler in the 80s? Uh, some of the utilities are in C, but compilers were slow and generated slow code back then, and it was quite noticable on a slow machine. When every byte of memory counts, you often need to hand-optimize.
My DOS computer from the 90s is sluggish with some of the more complex hand-written assembly things. C and UNIX were for powerful multi-user uses.
Roller Coaster Tycoon was written in assembly for optimization too.
The Amiga's OS was written in 68k asm and BCPL (C's grandfather) for the kernel, and C was used for the utilities and GUI. But this was considered quite ahead of its time for a single user micro.
Even today some parts need to be written in assembly, like context switches.
Most critical sections should be.
Yeah but the compilers weren’t that good at optimization back then.