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struct DHCP_std_params

The structure DHCP_std_params is declared in Dhcpcapi.h as below. The capitalized names in comments correspond to constants for these options.

typedef struct DHCP_std_params { 
   DWORD * subnet_mask;          // SUBNET_MASK 
   DWORD * dns_server;           // DNS 
   int     dns_server_len;       // length of dns 
   int     domain_name_len       // length of domain name 
   BYTE  * domain_name;          // DOMAIN_NAME 
   BYTE  * be_a_router;          // ROUTER_OPTION 
   WORD  * mdrs;                 // MDRS (maximum datagram reassembly size) 
   BYTE  * default_ip_ttl;       // DEFAULT_IP_TTL 
   WORD  * mtu;                  // PATH_MTU_AT 
   DWORD * static_route;         // STATIC_ROUTE_OP 
   int     static_route_len      // length of static route information 
   DWORD * router_option;        // ROUTER_OPTION 
   int     router_option_len;    // length of router option information 
   DWORD * arp_cache_timeout;    // ARP_CT_OP 
   BYTE  * tcp_default_ttl;      // TCP_DEFAULT_TTL 
   DWORD * tcp_ka_interval;      // TCP_KA_INTERVAL 
   BYTE  * tcp_ka_garbage;       // TCP_KA_GARBAGE 
} DHCP_std_params;

The fields in this structure are pointers into the DHCP message body. By taking the contents of these pointers, the value of the corresponding parameters can be accessed. For example, with:

static DHCP_session DS; 
static DHCP_conf    DC; 

Result = xn_dhcp(interface, &DS, &DC);

the MTU value returned by the server is accessed with:

if (Result != SOCKET_ERROR) 
   MTU = *DS.params.mtu;

DHCP Client

struct DHCP_param

Function XN_REGISTER_DHCP_CLI