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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: Suggested method for returning a string from a C program?
Date: Thu, 20 Mar 2025 12:28:27 -0700
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Michael S <already5chosen@yahoo.com> writes:
> On Thu, 20 Mar 2025 15:16:05 -0000 (UTC)
> Muttley@DastardlyHQ.org wrote:
>> On Thu, 20 Mar 2025 16:59:14 +0200
>> Michael S <already5chosen@yahoo.com> wibbled:
>> >On Thu, 20 Mar 2025 14:50:25 -0000 (UTC)
>> >Muttley@DastardlyHQ.org wrote:
>> >  
>> >> 
>> >> What makes you think they're macros?
>> >>   
>> >
>> >PRIu64 and PRId64 are macros. They are ugly.  
>> 
>> Never even heard of them. Looking them up I can't see much use for
>> them frankly except if you're starting out on an unknown system and
>> can't find out the info any other way which would be ... odd.
>
> Then how exactly do you printf value of type int64_t in a code that
> expected to pass [gcc] compilation with no warnings on two platforms,
> one of which is 64-bit Unix/Linux and another is just about anything
> else?

#include <stdint.h>
#include <stdio.h>
int main(void) {
    int64_t n = 42;
    printf("%ju\n", (intmax_t)n);
}

The alternative is:

#include <stdint.h>
#include <inttypes.h>
#include <stdio.h>
int main(void) {
    int64_t n = 42;
    printf("%" PRId64 "\n", n);
}

I was able to write the first from memory.  I had to consult the
standard for the second, though I'm sure I'd be able to remember it if I
used it more often.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */