TCPIP SOCKET-FUNCTION-GETHOSTBYADDR function fails with RSNCD 78891004. What is this error and where can I find USS TCPIP return/reason codes?

Document ID : KB000050232
Last Modified Date : 14/02/2018
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While trying to create a DC COBOL 'client' program using the example in the IDMS Callable Services manual COBCLI;

TCPIP SOCKET-FUNCTION-GETHOSTBYADDR function fails with Reason Code (RSNCD) 78891004.

What is this error and where can I find Unix System Services TCPIP return/reason error codes?


Go to the IBM Infocenter web page and choose the appropriate z/OS release

  • Chose the appropriate release under the section entitled "Publication titles, filenames, and order numbers by z/OS release"

  • Select the "List Books" link under the section entitled "z/OS diagnosis"

  • Select book "z/OS V1R11.0 UNIX System Services Messages and Codes".

  • The UNIX System Services Message and Codes, chapter 5 Reason Codes contains the Reason codes that are less than x'1000' whereas Reason codes greater than x'1000' can be located in the Common Services IP and SNA Codes in the chapter RESOLVER reason codes.

  • The ERRNOS can be found in the UNIX System Services Message and Codes, chapter 3 Return Codes (Errnos) Listed by Value.

If using z/OS 1.11 release; here's the link for the "Reason Codes":

The RSNCD 78891004 received by the GETHOSTBYADDR function consists of two halfwords:
The first halfword (7889) represent the UNIX component ID; the second halfword (1004) contains the reason code in hex (X'1004' or decimal 4100).

The X'1004' or decimal 4100 indicates "Resolver service did not find the specified host name".

When troubleshooting, check the IDMS Jes Log or the Common Services TCPIP log for additional messages.


CA IDMS Callable Services - A.0 Appendix A. TCP/IP Error Codes

  • A.1 Return, Errno, and Reason Codes
  • A.1.1 ERRNO Numbers Set By The Socket Program Interface
  • B.0 Appendix B. TCP/IP Programming Examples
  • B.4.1 COBOL TCP/IP Client Program

CA IDMS Release Summary - 6.3.1 System Generation TCP/IP Statement

  • 9.0 TCP/IP API Support
  • 9.3 TCP/IP Considerations
  • 9.3.3 Supporting DNS Functions Using the SYSTCPD File

CA IDMS System Tasks and Operator Commands - 4.59 DCMT DISPLAY TCPIP