Pelles C .chm documentation states
_setmode function
Declared in:
<io.h>
however, the definitions for the _setmode function "mode" parameter arguments
_O_BINARYetc.,
are not in
<io.h>but, instead, are located in
<fcntl.h>
The <io.h> header should
#include <fcntl.h>
https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/setmode?view=msvc-170 (https://learn.microsoft.com/en-us/cpp/c-runtime-library/reference/setmode?view=msvc-170)
Non standard function, for msvc, so follows ms specs ?
This is more about policy, I think. I document only the header file where the function prototype is located, because that was easy to start with.
Some functions will "need" more header files, some functions will need a #define <symbol> before the #include <...> to activate the prototype, but with over 1000 pages in the "C runtime" folder (not all of them related to functions, but anyway) it's a bit hard to find the energy just to begin investigating what to update (and how)...