ISPF editor

The ISPF editor is where mainframe code gets written. It edits a sequential dataset or one member of a library, and it works differently enough from a modern editor to be worth learning deliberately.

There are two places to type commands. The primary command line at the top takes commands that act on the whole file: find a string, change all occurrences, sort, save, cancel. The line command area down the left, where the line numbers are, takes short commands typed directly over the numbers: delete a line, repeat it, copy it, mark a block, shift text left or right.

That line command area is the part people find unusual and then miss everywhere else. Duplicating twenty lines is two keystrokes over a line number.

The editor also holds your changes in memory until you save, so cancelling discards them for good. Learning find, change, copy, move, insert and delete covers almost everything you will do day to day.