You create a memory file by defining the maximum number of rows and columns you will need for the memory file. The memory file, as initially defined, has no contents and is filled with empty rows. Empty rows are not displayed by the viewing functions. You must fill the rows by either (1) calling a function to transfer the lines of an ASCII disk file into the memory file or (2) placing a string in each row of the memory file.
You do not need to fill every row of the memory file with strings. The system keeps track of the last filled row in the memory file. You can place more information in the memory file at any time in your program.
In addition, you can limit the part of the memory file that is being viewed or operated on by means of keywords. A keyword is a special string that you place in the memory file to mark a single section. If you set the memory file to use that keyworded section, only that section is viewed, sorted, or otherwise operated on.
Subject only to memory limitations, you can have as many memory files as you want in your program. Memory use will be closely related to the amount of text in the file rather than the size of the memory file itself.
