about macros

[pber]

hi all,
i'm trying to switch from gcc,
mainly because PellesC it's very fast on compiling.

Does exist a way, in PellesC, to emulate the variadic macros of gcc?

thanks
paolo

[TimoVJL]

do you mean __VA_ARGS__ ?

[Snowman]

Does exist a way, in PellesC, to emulate the variadic macros of gcc?

http://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html

Variadic macros are part of the C99 standard, which Pelles C supports.
So you don't need to "emulate" them as if they're an extension to C.
Example:

#define eprintf(format, ...) fprintf (stderr, format, __VA_ARGS__)

[pber]

thanks, now I see the issue:

gcc allows to pass no arguments in place of <<...>>
i.e.: given

Code: [Select]

#define f(__fmt, ...) printf(__fmt, __VA_ARGS__)
you can use it with:

Code: [Select]

f("just a message\n");
but in case PellesC says:
Disagreement in number of macro arguments.

I cant' figure out how to deal with this...

[Snowman]

You can simply allow the ellipses (...) to include __fmt, then you can have one argument.

Example:

Code: [Select]

#include <stdio.h>

#define EPRINTF(...)    fprintf(stderr, __VA_ARGS__)

int main(void)
{
    EPRINTF("test 1\n");
    EPRINTF("%s %d\n", "test", 2);
}


[pber]

oh gosh.... it was so simple...
many thanks