sprintf for unsigned _int64
I am having following code. output of second %d in sprintf is always shown as zero. I think i am specifying wrong specifiers. Can any one help me in getting write string with right values. And this has to achieved in posix standard. Thanks for inputs
void main() {
unsigned _int64 dbFileSize = 99;
unsigned _int64 fileSize = 100;
char buf[128];
memset(buf, 0x00, 128);
sprintf(buf, "\nOD DB File Size = %d bytes \t XML file size = %d bytes", fileSize, dbFileSize);
printf("The string is %s ", buf);
}
Output:
The string is
OD DB File Size = 100 bytes XML file size = 0 bytes
Solution 1:
I don't know what POSIX has to say about this, but this is nicely handled by core C99:
#include <stdio.h>
#include <inttypes.h>
int main(void) {
uint64_t dbFileSize = 99;
uint64_t fileSize = 100;
char buf[128];
memset(buf, 0x00, 128);
sprintf( buf, "\nOD DB File Size = %" PRIu64 " bytes \t"
" XML file size = %" PRIu64 " bytes\n"
, fileSize, dbFileSize );
printf( "The string is %s\n", buf );
}
If your compiler isn't C99 compliant, get a different compiler. (Yes, I'm looking at you, Visual Studio.)
PS: If you are worried about portability, don't use %lld
. That's for long long
, but there are no guarantees that long long
actually is the same as _int64
(POSIX) or int64_t
(C99).
Edit: Mea culpa - I more or less brainlessly "search & replace"d the _int64
with int64_t
without really looking at what I am doing. Thanks for the comments pointing out that it's uint64_t
, not unsigned int64_t
. Corrected.
Solution 2:
You need to use %I64u with Visual C++.
However, on most C/C++ compiler, 64 bit integer is long long. Therefore, adopt to using long long and use %llu.
Solution 3:
If you are looking for a portable solution, then use printf macros from <inttypes.h>
. You may need to define __STDC_FORMAT_MACROS
to make these available in C++.