"char *array  declares an array of 256 char pointers. You have made no provisions for storage of actual characters, only the pointers. It is rather futile to duplicate argv in a local copy, since it is quite manipulable as it stands, even to the point of extending the lengths of strings to which it points.
Despite all that, you might want to copy argv, or copy the items which argv references. You need to tell us which of those things you want.
If you don't understand pointers, then refer to the link in my signature. Pointers are like entries in your address book; your girlfriend, or your data, does not live in your address book. They live at the location INDICATED in your address book. That location must exist, and be populated, or your address book isn't worth chit.