NicC wrote:... BTW, you do not have a file - or two - you have datasets.
NiC is absolutely right. The only
"file" in z?OS systems is the data between the beginning of a tape and a "file mark," or the data between two "file marks." A "file mark" on a magnetic tape, in turn is a special data record written in a way that ensures it will get the attention of the control units that operate a tape drive that it is not ordinary data.
By the way: it is "data sets" (yes, two words), not "datasets" (one non-existent word). A mistake I'm embarrassed to confess I too, have made.