By Graham K. Rogers

Ever since the first Macs appeared, they have been known for the graphical user interface (GUI): icons instead of command line work which before the mid-1980s was the norm. Paradoxically, the arrival of OS X brought with it easy access to the command line should users ever want this, although it is possible to use the computer without ever needing to work at the command line at all.

There are 1,384 commands on my Mac in Terminal. I may add to these later, but that is enough for now. In the BASH shell, we are able to discover this information by pressng the TAB key, then pressing TAB a second time.

A message appears on the screen, Display all 1384 possibilities? (y or n). Pressing n, will return the screen to the command line. Pressing y brings up a list of all the commands -- several pages long -- that are available. These are displayed one screen at a time and when the screen is full, at the bottom left is --More--

Pressing the space bar once will reveal the next page. When finished, the user will be returned to the command line.

But what do they all do?

There may be more information than we need to know, but this will indicate how flexible and powerful Unix is. In those entries, we can see that a lower case character is not the same as an upper case one.

Some manuals are long and while scrolling is done with the space bar, note the : to the left side of the screen, near the bottom. This allows a user to enter a command for the manual, such as q to Quit or h for help.

When the manual has completed scrolling, a bold (END) appears at the bottom left. To return to the command line, a user types in a colon -- : -- and the letter q.

There is much that can be done with the Unix in Terminal, but, especially if working in an Admin account, danger lurks if you are not sure what you are doing. If in any doubt, Don't.

I will examine some simple commands in the near future.

To be continued. . . .

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