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Network Address Resolution
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Data Structures

struct  pj_hostent
struct  pj_addrinfo

Defines

#define h_addr   h_addr_list[0]

Functions

pj_status_t pj_gethostbyname (const pj_str_t *name, pj_hostent *he)
pj_status_t pj_gethostip (int af, pj_sockaddr *addr)
pj_status_t pj_getdefaultipinterface (int af, pj_sockaddr *addr)
pj_status_t pj_getaddrinfo (int af, const pj_str_t *name, unsigned *count, pj_addrinfo ai[])

Detailed Description

This module provides function to resolve Internet address of the specified host name. To resolve a particular host name, application can just call pj_gethostbyname().

Example:

   ...
   pj_hostent he;
   pj_status_t rc;
   pj_str_t host = pj_str("host.example.com");
   rc = pj_gethostbyname( &host, &he);
   if (rc != PJ_SUCCESS) {
      char errbuf[80];
      pj_strerror( rc, errbuf, sizeof(errbuf));
      PJ_LOG(2,("sample", "Unable to resolve host, error=%s", errbuf));
      return rc;
   }
   // process address...
   addr.sin_addr.s_addr = *(pj_uint32_t*)he.h_addr;
   ...
 

It's pretty simple really...


Define Documentation

#define h_addr   h_addr_list[0]

Shortcut to h_addr_list[0]


Function Documentation

pj_status_t pj_getaddrinfo ( int  af,
const pj_str_t name,
unsigned *  count,
pj_addrinfo  ai[] 
)

This function translates the name of a service location (for example, a host name) and returns a set of addresses and associated information to be used in creating a socket with which to address the specified service.

Parameters:
af The desired address family to query. Valid values are pj_AF_INET(), pj_AF_INET6(), or pj_AF_UNSPEC().
name Descriptive name or an address string, such as host name.
count On input, it specifies the number of elements in ai array. On output, this will be set with the number of address informations found for the specified name.
ai Array of address info to be filled with the information about the host.
Returns:
PJ_SUCCESS on success, or the appropriate error code.
pj_status_t pj_getdefaultipinterface ( int  af,
pj_sockaddr addr 
)

Get the IP address of the default interface. Default interface is the interface of the default route.

Parameters:
af The desired address family to query. Valid values are pj_AF_INET() or pj_AF_INET6().
addr On successful resolution, the address family and address part of this socket address will be filled up with the host IP address, in network byte order. Other parts of the socket address are untouched.
Returns:
PJ_SUCCESS on success, or the appropriate error code.
pj_status_t pj_gethostbyname ( const pj_str_t name,
pj_hostent he 
)

This function fills the structure of type pj_hostent for a given host name. For host resolution function that also works with IPv6, please see pj_getaddrinfo().

Parameters:
name Host name to resolve. Specifying IPv4 address here may fail on some platforms (e.g. Windows)
he The pj_hostent structure to be filled. Note that the pointers in this structure points to temporary variables which value will be reset upon subsequent invocation.
Returns:
PJ_SUCCESS, or the appropriate error codes.
pj_status_t pj_gethostip ( int  af,
pj_sockaddr addr 
)

Resolve the primary IP address of local host.

Parameters:
af The desired address family to query. Valid values are pj_AF_INET() or pj_AF_INET6().
addr On successful resolution, the address family and address part of this socket address will be filled up with the host IP address, in network byte order. Other parts of the socket address are untouched.
Returns:
PJ_SUCCESS on success, or the appropriate error code.

 


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