Pascal III: SEEK

Pascal III: SEEK

SEEK has a problem when used with an Apple II Pascal formatted diskette.
When SEEKing a record that has been added to the file since the last RESET,
it either takes a long time to find the record, or else Pascal stops with a
System Failure error.
 
This commonly happens when you increase a file's size with PUTs and then
use a SEEK to access one of the new records.  Further operations on the file
may destroy it.
 
                 B L O C K   N U M B E R
        |   0   |   1   |   2   |   3   |   4  |
         ______________________________________
        |                   |                  |
        | Original file     | New information  |
        |___________________|__________________|
                            |                  |
                      EOF when RESET    Current EOF
 
For example: a SEEK to a record in the last half of block 2, block 3 or 4
causes undesirable results.
 
If you must extend a file, RESET the file before using SEEK.