To apply custom rules to a specific system or data set:
1. 'Add' a new row.
2. Click on the first column, and select your rules file.
3. Click on the second column, and write a DSN Mask.
This can be multiple masks, these must be separated by a comma ,

Example:
/var/jclexpert/samples/rule01.txt | USER.JCL.**
/var/jclexpert/samples/rule02.txt | SYS.JCL.**, ADMIN.JCL.**

When JCL Expert is run with a file under USER.JCL, rule01.txt is used.
When JCL Expert is run with a file under SYS.JCL, or ADMIN.JCL, rule02.txt is used.

To delete a row, clear the mask and press apply. The next time this window is shown the entry will be cleared.