Computer Programmin Chapter 5
trailer record
aka dummy data or sentinel value, contains a value in the particular field chosen for the loop test that is different form any possible valid value for the field
priming read
a READ statement that goes first , it geos the computer ready to make the loop test
detail line
a line of output associated with one input record
total line
a line that represents cumulative information form one or more input records.
automatic end-of-file facility
each programing language provides a specific way to implement this test. at design time simply noting that a check for an EOF condition is needed is sufficient
trailer record logic
last input record to the control the loop. this last record serves as a signal to the computer that no more records are to be processed
named constant
memory location whose content is not allowed to change during program execution
loop read
second READ statement, it is within the loop, usually the loop's last statement
heading line
serves as a title to a report
empty file condition
the test results will be true only if there is no input data