len might need to be shorter in strncpy(addr, ptr, len);

I got something like this:

(gdb) p ptr
$2 = 0xbfffee61 "95.251.46.206\004\b\b"

(gdb) p len
$3 = 256

This results in it showing garbage in the output:

$ ./ipfiy
95.251.46.206:

or

$ ./ipfiy
95.251.46.206m