On Wed, Apr 1, 2015 at 3:44 PM, Hansen, Dave L - Eagan, MN <[email protected]> wrote: > Dear Group, > > I get calls about CICS sockets and TN3270 sockets. When all I needed to > do was find out if an IP Address was up I just did a PING. Back when PING > went through the network end-to-end. > > I have been reading the z/OS V1R12.0 Comm Svr: IP Sockets Application > Programming Interface Guide and Reference. We now have z/OS V2R1. My REXX > EXEC can do a: src = socket("VERSION"); <== Figure 170. VERSION command > example. > > To use the socket commands provided by the REXX socket function, a socket > set must be active. To allocate a socket set, use the INITIALIZE socket > command. The INITIALIZE command creates a socket set and can support > multiple socket calls. > > In the book are a bunch of REXX socket sample programs <== Table 21. REXX > socket sample programs. In the book it says: "The LISTEN command applies > only to stream sockets". I would like to verify if I can hit my CICS Web > Services socket. My TCPIPSERVICE shows OPEN for PORT 1492. > > Q). Are CICS Web Services port 1492 and TN3270 port 23 "Stream sockets"?
Yes, TCP is a stream protocol over IP. Basically a "stream socket" is bit like a telephone. The client (caller) dials a number, the server (callee) must be "listening" for the phone to ring. The callee picks up the phone and says "hello" and you start talking. When you're finished, one side hangs up and so does the other. The other is a "datagram". It is a bit like a ham radio. The person on the radio does not know if anybody is listening or not. He just talks and hopes. He may, or may not, get any kind of response. Or maybe it's the old "message in a bottle". > > > Currently all is working. I would like my REXX EXEC to be non-disruptive > (and not cause a denial of service). The REXX socket sample programs use > INITIALIZE. It says it will preallocate a socket set. A socket set is a > number of pre allocated sockets available to a single REXX application. > > Q). Does my REXX EXEC need to have a socket to determine if one CICS socket > is working? The VERSION worked without specifying a socket number. If > anyone has done this before, are REXX socket functions the best way to "PING" > a TCP/IP PORT? > > > > Thank you, Dave -- If you sent twitter messages while exploring, are you on a textpedition? He's about as useful as a wax frying pan. 10 to the 12th power microphones = 1 Megaphone Maranatha! <>< John McKown ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
