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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c++
Subject: Re: uint32_t is not the same as long unsigned int ?
Date: Sat, 04 Jan 2020 02:16:28 -0800
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Jorgen Grahn <grahn+nntp@snipabacken.se> writes:
> On Sat, 2020-01-04, wolfgang bauer wrote:
>> A Question about Datatypes:
>>
>>
>> uint32_t x;
>>
>> printf("%lu\n", x);
>>
>> That results in this warning:
>>
>> warning: format '%lu' expects argument of type 'long unsigned int', but argument 2 has type
>> 'uint32_t {aka unsigned int}'
>
> Others have already explained the larger picture, but concretely:
>
> If you insist on combining std::printf and the fixed-width integer
> types, you need to use the PRI... macros from <cinttypes>,
> particularly:
>
>   #define PRIu32 "u"

*OR* you can convert to a type that you know is wide enough and that
printf handles directly:

    uint32_t x;
    std::printf("x = %lu\n", (unsigned long)x);

Or, of course:

    std::cout << "x = " << x << "\n";

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
    [Note updated email address]
Working, but not speaking, for Philips Healthcare
void Void(void) { Void(); } /* The recursive call of the void */