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Todays bug report is about newlib's snprintf() function

This example should return 0 but returns 4..

// --

#include <proto/dos.h>
#include <proto/Reactive.h>

#include <stdio.h>

int main( void )
{
TEXT buf[64];
int32 v;

buf[0] = 1;
buf[1] = 1;
buf[2] = 1;
buf[3] = 1;

v = snprintf( buf, 1, "1234" );

printf( "v %ld\n", v );
printf( "%d\n", buf[0] );
printf( "%d\n", buf[1] );
printf( "%d\n", buf[2] );
printf( "%d\n", buf[3] );

return( 0 );
}

Result looks like this

> tst.exe
v 4
0
1
1
1

No, it is correct. The snprintf() function always returns the number of characters it would have written had the buffer been large enough rather than how many characters it actually wrote. This is to allow you to easily check if the result was truncated by simply comparing the return value to the size of the buffer you used.

salass00 wrote:No, it is correct. The snprintf() function always returns the number of characters it would have written had the buffer been large enough rather than how many characters it actually wrote. This is to allow you to easily check if the result was truncated by simply comparing the return value to the size of the buffer you used.

ohh ya.. I was looking at sprintf()