Beyond a basic Oracle EXP/IMP shell script: Error Handling & Exit Status?

All,

• My skill level: I have written my share of shell scripts...mostly basic. A few "loops" and "if" statements here and there. 90% of my shell scripts have been to do things with Oracle; EXP/IMP, SQLPLUS, RMAN, etc. Mostly starting programs and handling external files. I have never written a case statement, nor used error handling (other than standard out).
• My task: I have been given the task/challenge to convert or add to existing EXP/IMP scripts error handling and return codes. I found some tutorials on the web and began playing with "trap" and "Exit status" in some basic shell scripts. I fear my biggest problem is that beyond "how to" I don't know what is possible (with shell scripts & Oracle).

OK, OK, OK...my task (specifically).
1.) I need to know (or test) if my script completes successfully and assign a value.

2.) I need to know if/where my script dies/aborts/terminates in the middle and assigning a value....rolling variable?

     "if step A complete then v_stats=...if step B complete then v_stats=..."

3.) I need to get a positive or negative return code from Oracle EXP/IMP utility and pass it to shell script (#2 above).

• Regarding Oracle EXP/IMP; Not sure what I am asking here...what are the possibilities if any for Oracle EXP/IMP utility return codes? And is a return code completely worthless anyway? Would I really need/parse/get the result "Export completed without warnings" to *know* the Oracle EXP/IMP returned successfully?

I'm all ears...and ready for code samples-scripts, docs, links and references.

Thanks,

Chris Marquez
Oracle DBA

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