z = strchr(buf, ' ') + 1;
while (isxdigit(z[0]) && isxdigit(z[1]) && (!z[2] || z[2] == ' ') &&
sscanf(z, "%x", &j) == 1 && j < 256)
z = strchr(buf, ' ') + 1;
while (isxdigit(z[0]) && isxdigit(z[1]) && (!z[2] || z[2] == ' ') &&
sscanf(z, "%x", &j) == 1 && j < 256)