sockaddr_iso address structure for the AF_ISO address family

With the AF_ISO address family, the name comprises a network selector NSEL and a transport selector TSEL. You use the sockaddr_iso address structure for the AF_ISO address family.

The sockaddr_iso structure is declared in the <iso.h> header as follows:

struct sockaddr_iso {
   u_char siso_len;            /* length of this sockaddr_iso structure*/
   u_char siso_family;         /* AF_ISO address family */
   u_char siso_plen;           /* length of presentation selector */
                               /* (is not supported; default: 0) */
   u_char siso_slen;           /* length of session selector */ 
                               /* (is not supported; default: 0) */
   u_char siso_tlen;           /* length of transport selector */
   struct iso_addr siso_addr;  /* ISO application address */
   u_char siso_pad[6];         /* is not supported*/
};
  
struct iso_addr {
   u_char isoa_len;            /* is not supported*/
   char isoa_genaddr[40];      /* complete address ( NSEL/TSEL ) */
};

The communications system for BS2000 expects a BCAM host name as the NSEL. The BCAM host name has a fixed length of 8 characters. Blanks are permitted at the end of the name, i.e. the name can be padded with blanks in order to achieve a length of 8 characters for NSEL. The transport selector TSEL can have a maximum length of 32 bytes. Because of the fixed length specifications for NSEL, you can use the transport selector length siso_tlen to select the transport selector from isoa_genaddr.

BCAM host name:

The name is eight characters in length. Alphanumeric characters and the special characters #, @, $ or blanks can be used at the end of the name. As a rule, uppercase characters should be used, but the name is case-sensitive. Names comprising numeric characters only are not permitted.