C/C++ 7.0 add on for OS/2

06 Jan 2024

Officially, the last version of Microsoft C to support OS/2 was version 6. C/C++ 7.0 was intended to support DOS and Windows development only, but also supported an add-on kit for developers who used OS/2 as a host platform to write applications. I had assumed this kit would be very rare - C/C++ 7.0 doesn't seem very common, and the add-on kit would only be interesting to a tiny portion of those users.

However, it turns out this add-on kit was included in Hobbes and many other distributions of OS/2 software. See "C7OS2.ZIP". This would not normally be useful on its own, because using it requires the headers and libraries from the base product.

That also means that the headers and libraries developed for Visual C++ 1.5 can be used with the C/C++ 7.0 add-on to compile 16 bit OS/2 programs using a natively hosted 16 bit OS/2 compiler, and none of the components from the base product are required.

Of course you should still own a copy of C/C++ 7.0 to use the OS/2 hosted add-on kit. Seeing it in Hobbes makes me wonder how many people used it without the base product though. I doubt I'm the first person to "discover" it can be used in this way, but back in 1992 people didn't have blogs to document their findings.