程序有警告

#include <stdio.h>


char strtobit(char str[]) {
    char result=0,i=0;

    for(i=0;str[i]!='\0';++i) {
        result = (result<<1) + str[i] - '0';
    }
    return result;
}



int main() {
    char source[]="ddssssasdfasdfasdfaqwfasdfawefasdfasdfawedasdfaw";

    int i=1,j=0;
    char tmp1[9];
    for(i=1;source[i]!='\0';++i)  {
        tmp1[j]=source[i];
        j++;
        if(i%8==0) {
        tmp1[j] = '\0';
        printf('%s', tmp1);
            printf('%c', strtobit(tmp1));
            j=0;
        }
    }
    getch();
}

就这么个程序，小弟是个初学者，编译器老说我的tmp1是个常量，运行的时候没有任何打印
[解决办法]

#include <stdio.h>
#include <conio.h> 

char strtobit(char str[]) {
    char result=0,i=0;

    for(i=0;str[i]!='\0';++i) 
{
        result = (result<<1) + str[i] - '0';
    }
    return result;
}



int main() {
    char source[]="ddssssasdfasdfasdfaqwfasdfawefasdfasdfawedasdfaw";

    int i=1,j=0;
    char tmp1[9];
    for(i=1;source[i]!='\0';++i)  
{
        tmp1[j]=source[i];
        j++;
        if(i%8==0) 
{
tmp1[j] = '\0';
printf("%s\n",tmp1);//应该是双引号
            printf("%c\n", strtobit(tmp1));//应该是双引号
            j=0;
        }
    }
    getch();//头文件应该包含#include <conio.h> 
}