ares_parse_ptr_reply man page
ares_parse_ptr_reply — Parse a reply to a DNS query of type PTR into a hostent
#include <ares.h> int ares_parse_ptr_reply(const unsigned char *abuf, int alen, const void *addr, int addrlen, int family, struct hostent **host);
The ares_parse_ptr_reply function parses the response to a query of type PTR into a struct hostent. The parameters abuf and alen give the contents of the response. The parameters addr, addrlen, and family specify which address was queried for; they are not used to verify the response, merely used to fill in the address of the struct hostent. The resulting struct hostent is stored in allocated memory and a pointer to it stored into the variable pointed to by host. It is the caller's responsibility to free the resulting host structure using ares_free_hostent(3) when it is no longer needed.
ares_parse_ptr_reply can return any of the following values:
The response was successfully parsed.
The response was malformatted.
The response did not contain an answer to the query.
Memory was exhausted.
Greg Hudson, MIT Information Systems
Copyright 1998 by the Massachusetts Institute of Technology.