PDM

PDM is an object and source managment system included as part of OS400. It comes with ADTS/400.

It is only available on a 5250 emulator. A next generation editor, beyond PDM, is Code/400. A previous generation editor before PDM, such as on S/36 SSP, was SEU which now is built inside of PDM.

PDM Commands

• From command line GO CMDPDM gets you a list of commands available to access PDM, such as editing programs, and other software objects.

• STRPDM, or Start PDM, launches menu of PPDM options

Option 23 FNDSTRPDM

A powerful feature of PDM is option 23 which can be used to search one file member or many members of a file, source physical, or database physical file for some character string. Optionally Case Sensitive. Like FIND in SEU it supports all types of access to members.

Option 54

A powerful feature of PDM is option 54 which can be used to compare two versions of the same program or other kind of object, to identify differences. Also see FCMU.

For example, you have some ERP software that came from some vendor, such as BPCS from SSA and you modified it, so now you have the original version, and your version. Then you get some patches or enhancements from SSA to some of the same programs that you modified. Now you need to get another copy of the software that has combined what just came from SSA and your modifications, and which may be further complicated by other employees having had a hand in this modification effort or even some outside consultants.

With PDM option 54 you can

• Compare original software to your past modifications to identify all the lines that got added, deleted, changed, and how many there were.
• Compare original software to the latest stuff from SSA to identify all that they did.

In one case, your company made 3,000 changes to the program, and SSA made 300, so in that case the obvious path is to copy your version, then modify it inserting copies of what SSA did. There will be cases where the numbers show a different course of action needed.

We keep earlier versions of software to support such comparisons, as needed, and just in case testing of a new version shows problems such that we need to revert to an earlier version.

There is also the scenario of too many cooks not doing such a hot job of communicating with each other. Several people have been working on modifications to this program and now we have several versions in different libraries, with several enhancements, none of which are in all the versions.

PDM 54 helps us make sense of what's where and what needs to be done to combine everyone's work into the final product.

Many people who did Y2K remediation might have been ignorant of this powerful tool.