z/XDC Assembler Development Tool

z/XDC is a powerful, interactive tool for developing and testing Assembler, C/C++ and Metal C language programs in the z/OS operating system.

z/XDC makes IBM's z/OS-based Assembler, C/C++ and Metal C languages easier to work with and understand. Using z/XDC, programmers can effectively find and correct errors in programs running in nearly any z/OS programming environment: authorized or nonauthorized, multitasking or single tasking, batch, TSO, or CICS, system exit or product exit, SVC routine or PC routine.

Key Abilities

SRB Mode Debugging

As IBM creates more and more SRB-only System Interfaces, the ability to debug them interactively becomes more and more valuable.

Comprehensive Mapping

z/XDC uses ADATA, SYM data and/or ESD data (whatever's available, whatever's necessary) for creating Linkedit/Binder maps, CSECT maps, and DSECT maps to help you visualize your code, data and control blocks.

PC Routine Debugging

PC Routines can be public or private, authorized or problem state, cross memory or not, whatever. z/XDC can debug them all.

Cross Memory Mode Debugging

z/XDC has extensive capabilities for debugging code with the Primary, Secondary and Home address spaces all being the same, or different in any conceivable way.

Also, z/XDC has full support for debugging programs that reach into above-the-bar storage or into data spaces.

Simple Control Block Maps

z/XDC provides DSECT maps for thousands of IBM control blocks. Creating DSECT maps for your own control blocks is trivially easy.

You can easily build floating structures of control block maps that dynamically adjust to representing the instance of current interest to your program.

Source Listing Support

z/XDC automatically loads source image maps (from ADATA), making your code in storage as easy to read as an assembly listing.

z/XDC also provides an assembly-time ADATA filtering tool that can reduce your ADATA library size up to ninety percent (90%)!



base/XDC is the core component of z/XDC. It consists of all the program development support that ColeSoft has spent over 40 years building.


auth/XDC is an optional feature that enables the ability to use z/XDC to debug programs running authorized and running in specialized environments.


asm/XDC is an optional feature that activates those z/XDC capabilities that are Assembler specific.


c/XDC is an optional feature that activates those z/XDC capabilities that are IBM XL C/C++ and Metal C specific.


Wondering if z/XDC will be a good tool for you? Take a look at what these industry leaders are saying about it!

Latest Product News

z/XDC's Built-in Help is now on the web! [woohoo!]

we have started publishing z/XDC's Built-in Help as web pages that are far more user friendly than z/XDC's classic HELP command. The pages contain...

XDCADATA Utility Improvements

The XDCADATA utility filters ADATA files to remove excess ADATA. When properly set up, size reductions up to 90% or more could be achieved. Two...

Major Performance Improvement for c/XDC users!

Starting with update DBC-2302H, c/XDC users will notice two things: They will quickly notice that the CWIDE and C80 profiles no longer display a...

Try z/XDC

ColeSoft offers a no-obligation, 60-day trial of z/XDC for prospective new users.

During the trial period, you will be able to install z/XDC, test it out, and evaluate whether z/XDC is a valuable tool for you. When you evaluate z/XDC, you will also be evaluating ColeSoft. We take our support role very seriously, and believe strongly in helping you get the most out of your investment in our product.