Hi!
sscanf returns 0 for the following code using musl, but glibc returns 1. %15s cannot be used here since it stops on whitespace, but it's required to get all remaining data after getting other fields with sscanf (not included in this example).
#include <stdio.h>
#include <string.h>
int main(void) {
char data[16];
memset(data, '\0', sizeof(data));
int res = sscanf("abcde", "%15c", data);
printf("parse: %d %s\n", res, data);
return 0;
}