Re: "A diagram of C23 basic types"

scott@slp53.sl.home (Scott Lurndal) writes:

bart <bc@freeuk.com> writes:

[...]

So it is not true that you need include stddef.h, nor obvious
that that is where NULL is defined, if you are used to having it
available indirectly.

>
Indeed, and it is well documented.
>
For example, in the POSIX description for the string functions
you'll find the following statement:
>
    [CX] Inclusion of the <string.h> header may also make visible
         all symbols from <stddef.h>.  [Option End]
>
This is true for a number of POSIX headers, include those you
enumerate above.
>
[CX] marks a POSIX extension to ISO C.

How strange.  I don't know why anyone would ever want either to
rely on or to take advantage of this property.  To make the extra
symbols visible, does there need to be something like

    #define __POSIX 1

to enable the non-conforming behavior?