PSC PT Program Generator - Manual (Page 159)

Finding the Number of Records in a File
User’s Guide
147
Finding the Number of Records in a File
The easiest way to determine the number of records in a file is to use a Verify
node with Match set to a value you know is not in the file and the Store Index
in Register checkbox selected (with a register specified for storing the index
value). Since it won’t find a match, the program will return the file size, storing
it in the index register.
Another method copies a known value to the end of the file, uses a Verify node
to locate it, and then subtracts 1 from the
Location Index . Tip07.scr,
illustrated in Figure 120 , demonstrates this method.
Figure 120. Tip07.scr Determines the Number of Records in a File
Display:
RECORDS Writes RECORDS= on the portable’s screen.
2342.book Page 147 Thursday, July 22, 2004 8:35 AM