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C (gcc/linux), 125 bytes
i;f(char*a){i=0;do{char*y=a,s[99],*x=inet_ntop(2,&i,s,99);for(;*x&&!(*x^*y&&*x^46);++x)y+=*x==*y;*x|*y||puts(s);}while(++i);}
Loops over all possible ip addresses, and does a custom comparison that skips over extra dots in the generated ip address (but not in the main ...