variable-arguments in c

variable-arguments.c

#include <stdarg.h>
#include <stdio.h>


void minprintf(char *fmt, ...);

void minprintf(char *fmt, ...) {
    va_list ap;
    char *p, *sval;
    int ival;
    double dval;
    
    va_start(ap, fmt);
    
//    
    for (p = fmt; *p; p++) {
        if (*p !='%') {
            putchar(*p);
            continue;
        }
        switch (*++p) {
            case 'd':
                ival = va_arg(ap, int);
                printf("%d", ival);
                break;
            case 'f':
                dval = va_arg(ap, double);
                printf("%f", dval);
                break;
            case 's':
                for (sval = va_arg(ap, char *); *sval; sval++)
                    putchar(*sval);
                break;
            default:
                putchar(*p);
                break;
        }
    }
    va_end(ap);
}
int main(int argc, char *argv[]) {
    
    minprintf("%d %f %s\n", 55, 23.4, "variable-arguments.c");
    return 0;
}