Check if 3270 connection to mainframe is available from C#?

Question

My company has an outsourcing partner that hosts data on a z series mainframe. Data is not in db2 but in some older structures. I guess vsam tables, if I haven't misunderstood those mainframe guys. We don't have ih-house knowledge of the mainframe technology. When we talk to partner's mainframe guys it sounds like they speak foreign language. We don't understand them, they don't understand us. PC world and mainframe world are quite different, yeah. We access data through 3270 terminal emulator (IBM Persona Communications). Teminal emulator does not connect directly to mainframe but rather to HIS 2000 Server (Microsoft Host Integration Server). HIS talks SNA to mainframe while clients talk tpc/ip to HIS server. We have an internaly developed helpdesk software (writen in c#) that monitors availability of other systems. Now we have request to extend the solution to monitor availability of the mainframe. The idea that we have is to start a 3270 session from our code. If connection suceeds system is available if not it's not available. We don't need to log in to mainframe and access any data there, just check if 3270 connection opens. I know this doesn't mean that actual data is available (sometimes data is locked by batch jobs and we can't access it even though system is up and running) but this approach is good enough for us. Could you point me to some documentation or existing projects? Can we use HIS or Personal Communications libraries. I haven't found any documentation on it.

Answer 1

Well, I finally got it.

I'm using Personal Communication api.
All functions exist in two dlls - pcsapi32.dll (pcsapi functions) and pcshll32.dll (ehllapi functions) that are part of Personal Communication installation. Everything is well documented in IBM documentation that can be found on

http://publib.boulder.ibm.com/infocenter/pcomhelp/v5r9/index.jsp?topic=/com.ibm.pcomm.doc/books/html/emulator_programming07.htm

or downloaded as pdf.

I had to p/invoke native windows functions and had no problems with it. Tried to use host access code library automation objects but had some issues with it and gave up.
Found usable code example at codeproject site http://www.codeproject.com/KB/cs/all_ehllapi.aspx

Answer 2

I am not sure if the solution I have would work for you. I used IBM PC Communicator Emulator and connected it to MS Excel using the APIs available for it. You can have a look at the APIs coding documentation here - http://publib.boulder.ibm.com/infocenter/pcomhelp/v5r9/index.jsp?topic=/com.ibm.pcomm.doc/books/html/emulator_programming07.htm.

If you need sample code to connect to MF from Excel via 3270 Emulator please let me know, I can provide the same to you.

Regards,

Nitin
nsrivastava2 [at] gmail.com