Parameter Substitution

Parameter substitution fundamentally works as string replacement utilizing a ‘compare to’ string and a ‘replacement string’ separated by an equal sign (‘=’). When the ‘compare to’ string is found, it is replaced by the ‘replacement string’. You can add or delete parameters from a given JCL command statement.

Parameter substitution now works by stripping off the comments and creating a logical line of a JCL statement that may have spanned several physical lines through use of continuation. The substitution is then applied against the logical line allowing for more flexible and specific substitution. The line is the re-broken into physical lines, following all the JCL syntax rules, and comments are re-inserted as it is written out to the modified JCL file.