Example Program

Let us write a program that uses the Simple Linkage convention. The program is to read three integers from the user and compute the sum. The outline of the program is:

# read first integer

# read second integer

# read third integer

# compute the sum

# write out the result

Of course, the user will enter integers as characters from the keyboard. The program uses the trap handler service number five to read the characters and convert it to a full word.