cctl

logical

Input 

True: Recognize carriage control, all formatted output (except unit 0)  

bzro

logical

Input 

True: Treat trailing and imbedded blanks as zeroes. 

apnd

logical

Input 

True: Open files at EoF. Append. 

prefix

character*n

Input 

Nonblank: For unit NN, seek and open file prefixNN

vrbose

logical

Input 

True: Report ioinit activity as it happens