Brush up some more code

libc/str/strncpy.c

@@ -24,39 +24,6 @@
  * 1. If SRC is too long, it's truncated and *not* NUL-terminated.
  * 2. If SRC is too short, the remainder is zero-filled.
  *
- * Please note this function isn't designed to prevent untrustworthy
- * data from modifying memory without authorization; the memccpy()
- * function can be used for that purpose.
- *
- * Here's an example of the only use case we know of for strncpy:
- *
- *     static const struct People {
- *       char name[8];
- *       int age;
- *     } kPeople[] = {
- *         {"alice", 29},  //
- *         {"bob", 42},    //
- *     };
- *
- *     int GetAge(const char *name) {
- *       char k[8];
- *       int m, l, r;
- *       l = 0;
- *       r = ARRAYLEN(kPeople) - 1;
- *       strncpy(k, name, 8);
- *       while (l <= r) {
- *         m = (l + r) >> 1;
- *         if (READ64BE(kPeople[m].name) < READ64BE(k)) {
- *           l = m + 1;
- *         } else if (READ64BE(kPeople[m].name) > READ64BE(k)) {
- *           r = m - 1;
- *         } else {
- *           return kPeople[m].age;
- *         }
- *       }
- *       return -1;
- *     }
- *
  * @return dest
  * @see stpncpy(), memccpy()
  * @asyncsignalsafe