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Back When Unions Were Useful

Posted on September 26, 2026 by dgookin
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Though it’s shunned today, using a union in your C code was common in the 1980s. Back then, compilers and IDEs such as Borland’s TurboC were customized for the MS-DOS operating system. Daring C programmers used the C language’s union keyword to access the system’s hardware directly. Scary.
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Posted in Lesson | Tagged dos.h, int86 function, union REGS | Leave a reply

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