You can get work done on a number of different ways on z. Some people prefer a fully graphical experience like what you get through Zowe. Other people like to keep it simple, but still want a little graphical contexts like what you get through the panels of ISPF. Then there's some people who really just don't want anything between them and the system, and they prefer to issue commands straight through TSO. In z/OS, TSO stands for time sharing option and it's basically the environment that lets the OS be made available to multiple users at the same time. There are a ton of commands in TSO. In this lesson, we're going to take a look at just a few of them. There are three primary ways of entering TSO commands. One, through the ISPF primary menu go into option number 6. Two, on the command option line of an ISPF panel on that line. Anything that starts with TSO, will be interpreted as a TSO command. Three, on the TSO ready prompt screen. When you do it this way, it's known as native mode. A command is made up of a command name, followed by one or more operands. Think of it like the command is the thing that you want done and the operands are the details of how you would like it to be done. For example, if I were to tell you move something, you would need more information like, what am I moving? Where I'm moving it to? am I moving with a forklift, a train, a truck, or am I just carrying it with my hands? The how, goes in the operands. Commands and operands, are not case sensitive, meaning, they can be typed out in lowercase or uppercase. We'll often type them out in uppercase though just so they stand out more as commands and not random text. There are two types of operands: positional and keywords. A positional operand, needs to come after the command and in a certain order. The documentation for commands, will tell you exactly what order they need to be in and which ones are required. We'll get into how you get that information shortly. There's also keyword operands. This is usually used to turn on a feature or set a certain mode. So in this example, the command is LISTDS. That's what we want it to do. We learned earlier that LISTDS, stands for list dataset and we can use it to show us a whole bunch of information about a dataset. The positional operand, is something that comes right after the command name. That's the dataset we're listing. One additional thing to note here. If what you want to put in the operand is a list of multiple items, you just put that list in parentheses. Then lastly, is the keyword operand. That tells the command to list the members of this dataset. For this lesson, we'll be referencing the z/OS, TSO/E command reference manual attached to this lesson. It's a good book. A lot better than the movie version. You can use the help command to obtain information about the function, syntax, and operands of the commands and subcommands, as well as information about certain messages. So you can type, HELP LISTDS OPERANDS and you'll get a listing of all the operands for the LISTDS command. You can also type HELP LISTDS ALL and you'll get all the information about the LISTDS command. In the next lesson, we'll take a look at the allocate and delete commands.
