Q1 ?perform para-d.? will cause a compiler error. para-d wasn?t defined.
?goto para b.? if not a typo, will cause a compiler error - s/b ?go to para-b.? And, of course, stmts 3&4 will never execute. Not necessarily an error, but unusual.
Q2 max rec len is 32K. The new LBI option allows very large blksizes for tape d/s. Only available for Assembler pgms.
Q3 Check the pre-compiler listing. If it shows ?CALL dataname? it?s a DYNAM call; if it shows ?CALL ?literal?? you have to check the compiler option (it could be either). Haven?t looked, but I?d guess they?re DYNAM calls.
Q4 Up to 255 bytes, but alt key len + offset can?t be GT base cluster?s data len.