by steve-myers » Tue 23 Jul 2013, 19:00
There are no user modifiable APF libraries. In other words, you cannot write authorized programs. Other than that, you can do pretty much anything you like that does not use APF restricted code.
The administrators will not tolerate wanna be MVS hackers. Any user that appears to attempt to damage the system in any way, even by accident, is "banned." The administrators will reinstate an ID if the perpetrator can persuade them it was all a mistake, but they are very hard nosed about this.
In general, you cannot access data sets belonging to another user. Attempts to do this generally result in your userid being "banned." One attempt is often ignored, but more than that is rarely ignored. This include attempts to update the master catalog.
Another activity that usually results in an ID being banned is if the administrator determine the ID is being used for training. Street corner "training" establishments, more often than not in 'BRAC" countries, seem to think they can offload training to Fandezhi. These IDs are usually quickly "banned" when this use is detected.
In response to TSUBLUH's post, SYS1.MODGEN is SYS1.MODGEN. TSUBLUH has been here long enough he should know this. You can browse the members and use it in an Assembler SYSLIB concatenation as much as you like. Personally, I've never figured out why some members, like IHAPDS, is there and not in SYS1.MACLIB. Similarly, IEFUCBOB is MACLIB, but it calls a number of MODGEN members.