need help about x25 protocol

[rajayashwanth]

hi everyone

here iam working with x25 protocol(dll),if any one have any idea about this protocol could u help me in the following querry.

actually in this x25 dll

x25data		
{		
OSINT	xd_len;	/* Length in bytes of xd_data */
char	xd_data[XD_DATALEN];	/* Data buffer address */
};

here is one of the method or function defined in that dll is x25xcall()

for that x25xcall() the following are the parameters.

public static extern unsafe int x25xcall(
			int *Cid,                    /* connection id */
			int X25NOWAIT,              /*waitmode flag*/
			int iPort,                 /*Portno of Eicon*/
			int iInfo,                 /*bit mask*/
		ref x25data sFacil ,           /*facility length and buffer*/
	    ref x25data sUsage ,           /*userdata length and buffer*/
			string Remote,             /*Remote DTE  address*/
			string Local,              /*Local DTE  address*/
			PostDelegate post, 
			IntPtr xi_ref);/

for this sfacil parameter,which values i have to pass.

please help me