By specifying TYPERUN=SCAN on a job card or by executing JSCAN, it is possible to examine JCL syntax without actually running the programme. The TYPRUN command is used to request specific job processing, such as checking or scanning a task for syntax mistakes.  This is one example of what may be done with this command. SCAN examines the code for any syntax mistakes but does not carry out the task itself. In every other case, JSCAN is able to verify the syntax of a JCL without actually executing it.