Return a pointer to that NUL-terminated string in malloc'd storage.
If readlink fails, return NULL (caller may use errno to diagnose).
If malloc fails, or if the link value is longer than SSIZE_MAX :-),
give a diagnostic and exit. */
char *
Return a pointer to that NUL-terminated string in malloc'd storage.
If readlink fails, return NULL (caller may use errno to diagnose).
If malloc fails, or if the link value is longer than SSIZE_MAX :-),
give a diagnostic and exit. */
char *