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4 of 4 added 9 characters in body

C, 230 200 193 characters

EDIT: Shortened it from 230 to 193 characters.

My first golf attempt. Maybe not a hole-in-one, but it works. Not being allowed to use strlen for this forces it to be fairly verbose in C. Maybe it can be shortened a bit?

a,b,w,i,l;
int main(int c,char **v){
    for(;a<256||b<256;i++){
        if(!v[1][i])a|=256;
        if(!v[2][i])b|=256;
        if(!(a&256))a++;
        if(!(b&256))b++;
    }
    a&=255;b&=255;
    w=a>b?0:1;
    l=w?b-a:a-b;
    printf("%s %i\n",v[w+1],l);
}

Or the uglier version:

a,b,w,i,l;int main(int c,char **v){for(;a<256||b<256;i++){if(!v[1][i])a|=256;if(!v[2][i])b|=256;if(!(a&256))a++;if(!(b&256))b++;}a&=255;b&=255;w=a>b?0:1;l=w?b-a:a-b;printf("%s %i\n",v[w+1],l);}

Example output:

N:\>golf.exe everything works
everything 5