getipnodebyname,  getipnodebyaddr,  freehostent - get network hostnames
   and addresses


   #include <sys/types.h>
   #include <sys/socket.h>
   #include <netdb.h>

   struct hostent *getipnodebyname(const char *name, int af,
                                   int flags, int *error_num);

   struct hostent *getipnodebyaddr(const void *addr, size_t len,
                                   int af, int *error_num);

   void freehostent(struct hostent *ip);


   These  functions  are  deprecated  (and  unavailable  in  glibc).   Use
   getaddrinfo(3) and getnameinfo(3) instead.

   The  getipnodebyname() and getipnodebyaddr() functions return the names
   and addresses of a network host.  These functions return a  pointer  to
   the following structure:

       struct hostent {
           char  *h_name;
           char **h_aliases;
           int    h_addrtype;
           int    h_length;
           char **h_addr_list;

   These  functions  replace  the  gethostbyname(3)  and  gethostbyaddr(3)
   functions, which could access only the  IPv4  network  address  family.
   The   getipnodebyname()  and  getipnodebyaddr()  functions  can  access
   multiple network address families.

   Unlike the gethostby functions,  these  functions  return  pointers  to
   dynamically  allocated  memory.   The freehostent() function is used to
   release the dynamically allocated memory after  the  caller  no  longer
   needs the hostent structure.

   getipnodebyname() arguments
   The  getipnodebyname() function looks up network addresses for the host
   specified by the name argument.  The af argument specifies one  of  the
   following values:

          The name argument points to a dotted-quad IPv4 address or a name
          of an IPv4 network host.

          The name argument points to a hexadecimal IPv6 address or a name
          of an IPv6 network host.

   The  flags argument specifies additional options.  More than one option
   can be specified by bitwise OR-ing them together.  flags should be  set
   to 0 if no options are desired.

          This  flag  is  used  with  AF_INET6 to request a query for IPv4
          addresses instead of IPv6 addresses; the IPv4 addresses will  be
          mapped to IPv6 addresses.

   AI_ALL This  flag  is used with AI_V4MAPPED to request a query for both
          IPv4 and IPv6 addresses.  Any IPv4 address found will be  mapped
          to an IPv6 address.

          This  flag is used with AF_INET6 to further request that queries
          for IPv6 addresses should not be made unless the system  has  at
          least one IPv6 address assigned to a network interface, and that
          queries for IPv4 addresses should not be made unless the  system
          has  at  least one IPv4 address assigned to a network interface.
          This flag may be used by itself or with the AI_V4MAPPED flag.

          This flag is equivalent to (AI_ADDRCONFIG | AI_V4MAPPED).

   getipnodebyaddr() arguments
   The getipnodebyaddr() function looks up the  name  of  the  host  whose
   network  address  is  specified  by the addr argument.  The af argument
   specifies one of the following values:

          The addr argument points to a struct in_addr and len must be set
          to sizeof(struct in_addr).

          The  addr  argument  points to a struct in6_addr and len must be
          set to sizeof(struct in6_addr).


   NULL is returned if an error occurred, and error_num  will  contain  an
   error code from the following list:

          The hostname or network address was not found.

          The  domain  name server recognized the network address or name,
          but no answer was returned.  This can happen if the network host
          has  only  IPv4  addresses  and a request has been made for IPv6
          information only, or vice versa.

          The domain name server returned a permanent failure response.

          The domain name server returned a  temporary  failure  response.
          You might have better luck next time.

   A  successful  query  returns  a  pointer  to  a hostent structure that
   contains the following fields:

   h_name This is the official name of this network host.

          This is an array of pointers to unofficial aliases for the  same
          host.  The array is terminated by a null pointer.

          This  is  a  copy  of  the  af  argument to getipnodebyname() or
          getipnodebyaddr().  h_addrtype will always be AF_INET if the  af
          argument was AF_INET.  h_addrtype will always be AF_INET6 if the
          af argument was AF_INET6.

          This field will be set to sizeof(struct in_addr)  if  h_addrtype
          is  AF_INET,  and  to  sizeof(struct  in6_addr) if h_addrtype is

          This is an array of one or  more  pointers  to  network  address
          structures  for  the network host.  The array is terminated by a
          null pointer.


   RFC 2553.


   These functions were present  in  glibc  2.1.91-95,  but  were  removed
   again.   Several  UNIX-like  systems  support  them,  but all call them


   getaddrinfo(3), getnameinfo(3), inet_ntop(3), inet_pton(3)


   This page is part of release 4.09 of the Linux  man-pages  project.   A
   description  of  the project, information about reporting bugs, and the
   latest    version    of    this    page,    can     be     found     at


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