Re: *printf declarations in stdio.h?

[Bruno Haible]

Simon Josefsson wrote:
>  How about this?
> 
> /Simon
> 
> 2007-03-13  Simon Josefsson  <address@hidden>
> 
>       * m4/stdio_h.m4: Add stubs for vasprintf too.
> 
>       * modules/stdio: Support vasprintf in sed command.
> 
>       * modules/vasprintf: Depend on stdio for prototypes, and remove
>       vasprintf.h.
> 
>       * lib/stdio_.h: Declare asprintf and vasprintf, based on
>       vasprintf.h.
> 
>       * lib/asprintf.c: Use stdio.h for prototypes.
>       * lib/vasprintf.c: Ditto.
> 
>       * lib/vasprintf.h: File removed.
> 
>       * tests/test-vasprintf-posix.c: Use stdio.h instead of vasprintf.h.
>       * tests/test-vasprintf.c: Ditto.
>       * lib/xvasprintf.c: Ditto.

Better but still incomplete:

> +# if @REPLACE_VASPRINTF@ || address@hidden@
> +  /* Write formatted output to a string dynamically allocated with malloc().
> +     If the memory allocation succeeds, store the address of the string in
> +     *RESULT and return the number of resulting bytes, excluding the trailing
> +     NUL.  Upon memory allocation error, or some other error, return -1.  */
> +  extern int asprintf (char **result, const char *format, ...)
> +    __attribute__ ((__format__ (__printf__, 2, 3)));
> +  extern int vasprintf (char **result, const char *format, va_list args)
> +    __attribute__ ((__format__ (__printf__, 2, 0)));
> +# endif

Why here you use @HAVE_DECL_VASPRINTF@ where the original code used
HAVE_VASPRINTF? Did you encounter a platform which has the same vasprintf()
but doesn't declare it? vasprintf is not a standardized, therefore I can well
imagine a platform which has a vasprintf that returns a 'char *' instead
of 'int' - then testing HAVE_VASPRINTF is safer.

And I don't see any m4/* code that would set the shell variable HAVE_VASPRINTF
or HAVE_DECL_VASPRINTF to 0. It is only ever set to 1, which is not the
intent.

Bruno