DLPI Programmer's Guide

Appendix A 153
Sample Programs
Connection Mode
*/
disc_req->dl_correlation = 0;
/* send the disconnect request */
put_ctrl(fd, sizeof(dl_disconnect_req_t), 0);
/* wait for the OK_ACK */
get_msg(fd);
check_ctrl(DL_OK_ACK);
}
/**************************************************************************
main
**************************************************************************/
main() {
int send_fd; /* file descriptor for sending stream */
int recv_c_fd; /* fd for recv ctrl stream */
int recv_d_fd; /* fd for recv data stream */
u_char sdlsap[20]; /* sending DLSAP */
u_char rcdlsap[20]; /* receiving control DLSAP */
u_char rddlsap[20]; /* receiving data DLSAP */
int sdlsap_len, rcdlsap_len, rddlsap_len; /* DLSAP lengths */
u_long correlation; /* correlation number for CONNECT_IND */
u_long token; /* token for recv_d stream */
int i; /* loop counter */
/*
We'll use three streams: a sending stream, a receiving stream bound
with max_conind = 1 (the ”control” stream), and a receiving stream
bound with max_conind = 0 (the ”data” stream). The connect indication
will be handed off from the control stream to the data stream.
We initially open only the sending stream and the receiving control
stream.
*/
/*
First, we must open the DLPI device file, /dev/dlpi, and attach
to a PPA. attach will open /dev/dlpi, find the first PPA
with the DL_HP_PPA_INFO primitive, and attach to that PPA.
attach() returns the file descriptor for the stream.
*/
send_fd = attach();
recv_c_fd = attach();
/*
Now we must bind the streams to saps. The bind function will
return the local DLSAP and its length for each stream in the last
two arguments. Only the receiving control stream has a non-zero
max_conind.
*/
bind(send_fd, SEND_SAP, 0, DL_CODLS, sdlsap, &sdlsap_len);
bind(recv_c_fd, RECV_SAP, 1, DL_CODLS, rcdlsap, &rcdlsap_len);
/*
Start the connection establishment process by sending a CONNECT_REQ
from the sender to the receiver control stream.
*/