You had possible checked this thing before. IBM is providing some documentation for OS/2 in the developerworks site.
To download this documentation you need a free registration to Developerworks.
http://www6.software.ibm.com/devcon/devcon/docs/catalog.html
OS/2
* Configuration, Installation, and Distribution (CID) Enabling Guidelines (G Web-only)
* DBCS Design Guide and Information for OS/2 Warp 4 Programming (G Web-only)
* DHCP and Dynamic IP Client Administration Guide (G Web-only)
* DOS LAN Services User's Guide (G Web-only)
* IBM LAN Technical Reference (G Web-only)
* IBM OS/2 Multimedia Installation and Configuration Guide (G Web-only)
* IBM PC LAN Program Migration Guide (G Web-only)
* IBM User's Guide to OS/2 Warp (G Web-only)
* IBM Writing for an International Audience (G Web-only)
* Memory Debugging for C and C++ Programs (G Web-only)
* OS/2 Bidirectional Language Support Developer's Guide and Reference (G Web-only)
* OS/2 Debugging Handbook 0.7a (P Web-only)
* OS/2 Server Family Programming Reference (G Web-only)
* OS/2 Warp Dynamic DNS Implementation Guide (G Web-only)
* Procedures Language 2/REXX User's Guide (G Web-only)
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