NAME

getsockopt − Obtain HDLC, LAPB, or LLC2 Link information

SYNTAX

#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netdnet/dli_var.h>
#include <wdd/hdlc_var.h>

getsockopt (s, level, optname, optval, optlen)
int s, level, optname;
char ∗optval;
int; ∗optlen;

DESCRIPTION

This system call allows you to obtain Link information. The information returned contains:

        Link status
        Frame size
        Service Data Unit (SDU) status
        User XID data

(see the DEC WAN Device Drivers Application Programmer’s Guide for a complete description of the link information returned.) 

ARGUMENTS

Input Arguments

s descriptor for a socket

level DLPROTO_HDLC, DLPROTO_LAPB, or DLPROTO_LLC2

optname HDLC_SHOWLINK
 

optval address of the buffer that will contain the returned value of the link status

optlen size of the data structure

RETURN VALUE

If the call succeeds, a value of 0 is returned.  If an error occurs, a value of -1 is returned.  Additional error detail is specified in the external variable errno.

DIAGNOSTICS

[EIDRM] The port has been either closed or needs to be closed

[ENETDOWN] The line has been disabled. 

[ENXIO] The specified port does not exist

SEE ALSO

socket(2h), setsockopt(2h), read(2h), recv(2h), send(2h), write(2h), close(2h).