brk
extern int brk(void *addr);
int i, j, v, d, brk=-1, need_v4=0;
if (s[0]==':' && brk<0) {
brk=i;
if (!s[j] && (brk>=0 || i==7)) break;
if (s[j]!='.' || (i<6 && brk<0)) return 0;
if (brk>=0) {
memmove(ip+brk+7-i, ip+brk, 2*(i+1-brk));
for (j=0; j<7-i; j++) ip[brk+j] = 0;