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struct DHCP_conf

By setting the fields in the DHCP_conf structure pointed to by the conf parameter in xn_dhcp, an application can control the DHCP client behavior. It is recommended to always initialize a DHCP_conf structure with xn_init_dhcp_conf and then make modifications as needed (if any).

The structure is declared as follows:

struct DHCP_conf 
{ 
   DHCP_param * plist; 
   int           plist_entries; 
   DHCP_cparam * cplist; 
   int           cplist_entries; 
   int           request_std_params; 
   int           apply_std_params; 
   DWORD         lease_time;            // seconds 
   BYTE          client_ip_addr[4]; 
   BYTE          req_ip_addr[4]; 
   BYTE *        vendor_specific; 
   int           vs_size; 
};

To fill in the fields of this structure, use the following rules:

A DHCP_conf variable must be allocated as a global or static variable and it must not be modified after xn_dhcp has been called.

If you already know your IP address, and are using DHCP only to obtain network configuration parameters:

• Set client_ip_addr to your IP address.
• DO NOT set the req_ip_addr field.

If you do not know your IP address, and are using DHCP to obtain an IP address lease:

• DO NOT set the client_ip_addr field.
• If you have a specific IP address that you would like to be assigned to, set the req_ip_addr field to that address. Otherwise, do not set the req_ip_addr field. A DHCP server may or may not give you the address you request.

If you want to request a specific IP address lease time:

• Set the lease_time field to the desired lease time in seconds. DHCP_INF_LEASE (0xFFFFFFFF specifies infinite lease time).

If you do not want to use the standard DHCP parameters to be requested from the server:

• Set request_std_params to FALSE.

If you do not want to use the standard DHCP parameters that are returned by the server to be automatically applied:

• Set apply_std_params to FALSE.

If you are requesting the standard DHCP parameters and want to request other parameters as well, or if you are not requesting the standard parameters and want to specify your own list of parameters to request:

• Set plist to the address of an array of struct DHCP_param.
• Set plist_entries to the number of elements in the array.

If you want to include vendor specific information in the outgoing DHCP packet:

• Set the vendor_specific field to point to the chunk of vendor specific information.
• Set the vs_size field to the size (in bytes) of the vendor specific information.

DHCP Client

DHCP Client Configuration

struct DHCP_param