Joined: 06 Jun 2008 Posts: 8553 Location: Dubuque, Iowa, USA
Some of what you ask can easily be answered by a quick Google search -- have you tried Google yet?
1. Transaction deadlock occurs when transaction A has exclusive use of resource Z and needs resource Y to complete, while transaction B has exclusive use of resource Y and needs resource Z to complete. Neither transaction can continue. READ for UPDATE, for example, requires exclusive access to the VSAM CI you are updating. There are other ways to force exclusive use of a resource.
2. Compiler options are specific to COBOL (or whatever language you are using for CICS) and would include things like RENT or DYNAM -- most of what you mentioned in your post would not be considered compiler options.
3. Wouldn't the answer depend upon YOUR experience? Things like ASRA, AICA, APCT, 4088 -- depending upon your experience -- are all quite possible and common.
4. DFHCOMMAREA cannot be more than 32K and IBM recommends using 26K or less (IIRC -- it's been a while since I checked their documents last). This is due to the half-word (2 bytes) used for the length.
5. Files in CICS are not opened by the program but by CICS. They can be opened at CICS start up or when the file is first referenced.
6. You'll get a non-zero response code (assuming your code uses RESPONSE) -- INVREQ usually (unless there's something else causing a different code). The update will NOT be applied to the file.
Knowing the answers to specific questions about CICS will not typically help you much in an interview -- any follow up questions would quickly determine that your knowledge is quite limited.