Find what each control card deck is

Report what kind of deck each control card member holds — DFSORT or ICETOOL statements, IDCAMS commands, Db2 utility control statements, a DSN command deck, or cards no grammar here reads yet — with the steps that read it, and mark each statement in the source. A control card library is one library holding several languages, and a member's name says nothing about which it is, so each is typed by its first statement; a deck written in a job stream is typed the same way, under the job it is written in. Two kinds of edge come out of it: the member each SYSIN resolves to, which is the only word the DD and the library share, and the data sets an IDCAMS DEFINE creates — the one place a VSAM file's existence, key and record size are written down, since the JCL that reads the file names only a DD and the COBOL names only that. AnalyzeControlCards answers the same question and changes nothing.