Connectivity reference

HTML coded character sets
This reference lists the supported IANA-registered character set names (specified as charset= values in HTTP headers), and the IBM® CCSID equivalents.
HTTP header reference for CICS web support
In CICS® web support, CICS automatically provides some HTTP headers on outbound messages and you can also add your own headers. When messages are sent to CICS, CICS takes action in response to some HTTP headers, and a user application program can take action in response to others. This reference information describes how CICS web support handles HTTP headers.
HTTP status code reference for CICS web support
HTTP status codes are provided to clients by a server, to explain the consequence of the client's request. When CICS is an HTTP server, depending on the circumstances, either CICS web support or the user application program selects an appropriate status code for each response. When CICS is an HTTP client, most status codes received from the server are passed to the user application program for handling.
HTTP method reference for CICS web support
HTTP requests include a method, which is a keyword explaining the action that the client wants the server to perform for the material included in the request. CICS web support implements all the standard request methods defined by the HTTP/1.1 specification, and some additional methods that were accepted in earlier CICS releases.
Elements used in an Atom configuration file
The XML elements used in an Atom configuration file define the type of Atom feed that is being configured and the location of the CICS resource that provides the Atom feed, and they provide the metadata required for the Atom feed. These elements can be added to an Atom configuration file using the Atom configuration wizard in CICS Explorer®. They can also be edited using the Atom configuration editor in CICS Explorer, or by editing the Atom configuration file directly using an XML editor or a text editor.
Reference information for analyzer programs
This topic provides reference information for analyzer programs, including input and output parameters, and responses and reason codes.
Converter programs
Converter programs are primarily for use with application programs that were not originally coded for use with the web. They can also be used to combine output from several application programs into a single HTTP message. Converter programs are not used when CICS is an HTTP client, or for web service processing; they can only be invoked when CICS is an HTTP server.
Reference information for DFHWBBLI, CICS business logic interface
The business logic interface allows callers to specify what presentation logic is to be executed before and after a CICS application program. It has two modes of operation, pointer mode and offset mode.
Reference information for DFHWBEP, web error program
DFHWBEP receives a parameter list from CICS, giving information about the error situation, and a block of storage containing the default HTTP response, including status code and status text, that CICS plans to send to the web client. The program can use or modify the default response or create and send its own response using the EXEC CICS WEB and DOCUMENT API commands.
The DFHWBCLI Web Client Interface
DFHWBCLI is a CICS-supplied utility program that you can invoke by EXEC CICS LINK to provide web client services or outbound HTTP. This program is deprecated. The functions of the DFHWBCLI Web Client Interface are retained for compatibility reasons. To gain enhanced functionality, you can upgrade existing HTTP client applications that used the DFHWBCLI interface, to use the EXEC CICS WEB API commands for client requests (with the SESSTOKEN option). When you develop new web applications, you should use the EXEC CICS WEB API commands and associated URIMAPs; do not use DFHWBCLI.
Reference information for DFH$WBST and DFH$WBSR, state management samples
Two state management sample programs, DFH$WBST and DFH$WBSR, are supplied with CICS web support. They allow a transaction to save data for later retrieval by the same transaction, or by another transaction.
Conversion CCSIDs for CICS TS
The code page conversion groups for the supported Coded Character Set Identifiers (CCSIDs) are listed. CCSIDs are provided for code page conversion for use with the DFHCCNV conversion program.
How it works: Data conversion in CICS
This section describes in more detail how data conversion works in CICS.
Intercommunication rules and restrictions checklist
This appendix provides a checklist of the rules and restrictions that apply to intersystem communication and multiregion operation.
CICS mapping to the APPC architecture
This reference section shows how the APPC programming language is implemented by CICS.
Migrating LUTYPE6.1 applications to APPC links
If your installation is changing its CICS-to-CICS Intersystem communication (ISC) links from LUTYPE6.1 to APPC (LUTYPE6.2), you may want to redesign some of your existing ISC applications to take advantage of APPC function. Alternatively, you can continue to run your existing applications in migration mode.
Differences between APPC mapped and MRO conversations
When a SEND command is issued on an MRO session, CICS does not defer sending the data, so control indicators cannot be added to the data after a SEND command has been issued. The same command sequence may therefore require more flows on an MRO session than it does on an APPC session but, if the receiving transaction is correctly designed to be driven by the conversation state, the same effects are achieved.
Below the SNA interface
To design high-performance distributed processes, you need some understanding of the SNA protocols and corresponding data flow control (DFC) indicators that CICS uses for DTP, and how the DFC indicators relate to the CICS commands and options. In addition, you need this knowledge to understand the CICS trace.