No, it’s impossible. What you suggest assumes that nobody will ever purposely #include something twice. However, this is not true. For example, consider this foo.h:

#ifdef MAKE_FOO_BE_BAR
# undef MAKE_FOO_BE_BAR
# define foo bar
#else
# undef foo
# define MAKE_FOO_BE_BAR
#endif

Now imagine a foo.c that includes this multiple times:

#include <stdio.h>
void foo() { printf( “foo\n” ); }
void bar() { printf( “bar\n” ); }
int main()
{
#include “foo.h”
foo();
#include “foo.h”
foo();
#include “foo.h”
foo();
}

This prints:
foo
bar
foo

Admittedly, this is a contrived example. But, I’ve heard of at least one assert.h which used a similar trick such to cause multiple includes to toggle assertions. (My system’s assert.h does *not* exhibit this behavior.)

-Mark

-molo

PS: had problems with spam bots posting here? whats with the capcha?

No, I haven’t, but mostly because I need to #include “windows.h” , etc, and I have no idea how to use MinGW or Cygnus to do this with gcc on Windows.

From reading the man page, it sounds rather similar to VisualC’s -P switch. In other words, it gives me the preprocessed output file. What I wanted, but later discovered was impossible, was to only process #include directives, and leave all the #ifdef stuff alone.

-Mark

have you tried using gcc -save-temps?