text: A good use of this program is for an application that must pull an index from a source other 
  than the document. The application group can be set up with a default index; then, the user 
  exit program can grab the appropriate index from this secondary source and replace the 
  default value that was in the index record. The record is then sent back to ACIF. 
  
  Another example is to modify the format of an existing index. Example 11-1 shows a sample 
  index exit C program to update the date format from mmddyy to mm/dd/yy. 