Mainframe, MVS and zOS Discussion

Is there any rule of thumb to be followed when we write a new CICS program and choose one from COMMAREA, TDQ or TSQ? Or it is like COMMAREA will always be there and choice between TDQs or TSQs depends on the application requirement?
Regards,

But none of them is a CBT. All are reference materials only.

Understand that it was a joke but is it that virus never attacked mainframe becuause it never had general users using it? And it is used only by "maintainence" programmers?

Hi,

Does anyone know of a place to get any computer based trainign material (CBT) for PL/1 or assembler. I have searche dthe IBM site but they have big reference manauls.

William Collins wrote:Because Punched Cards are "read only".

But we don't use punch cards. All is on computers now. And for many comapnies it is outsourced but it is still secured?

Hi,

Why it is always said that the mainframe is so secure and the virus can't affect the mainframe? Historically is this never happened?