CICS Web support and 3270 display applications

When a 3270 transaction is accessed by a Web client, CICS® can display the output as an HTML form. Use the variants of the Web Terminal Translation Application (DFHWBTTA, DFHWBTTB or DFHWBTTC) to provide Web clients with access to applications that were originally designed to use the 3270 display system.

Attention: This topic contains Product-sensitive Programming Interface and Associated Guidance Information.
An HTML form can be created from the output of a 3270 transaction in one of two ways:
The Web Terminal Translation Application can be used to display the HTML forms to a Web browser.
Note: Start of changeThe Web Terminal Translation Application operates at HTTP/1.0 level. It does not make full use of the facilities available in CICS Web support (such as the EXEC CICS WEB API), and so does not provide compliance with the HTTP/1.1 specification. This means that:
  • Requests from the Web client, and responses from the application, are not checked against the HTTP protocol specification.
  • CICS does not provide HTTP/1.1 responses, in normal or error situations, even if the client is at HTTP/1.1 level.
End of change
All three variants of the Web Terminal Translation Application support non-conversational, conversational, and pseudoconversational transactions. DFHWBTTB and DFHWBTTC are aliases for DFHWBTTA; the same program (DFHWBTTA) is invoked in each case. CICS uses the name by which the program is invoked to determine which processing is needed.

DFHWBTTA, DFHWBTTB and DFHWBTTC generate HTML that conforms to the HTML 3.2 specification. If you use a Web browser that does not support HTML 3.2, some functions may not work correctly.

Start of changeHTML generated for terminals having a pagesize which results in a field position greater than 4095 (x'FFF') might not function correctly, particularly when using DFHWBTTC. The exception to this is when using old style templates. (Old style templates are those generated by DFHWBTLG from CICS TS 1.2 or CICS TS 1.3 before PTF UQ53534). Code has been supplied to tolerate BMS sends of such templates when using DFHWBTTA or DFHWBTTB, but not DFHWBTTC. End of change

Start of changeYou can create URIMAP definitions that specify DFHWBTTA, DFHWBTTB or DFHWBTTC as the program to be invoked to process a request (PROGRAM attribute). The method that the Web client uses to access the program is similar, but the use of URIMAP definitions gives you an online administration facility that can be used to prevent or redirect requests. When a URIMAP definition is used, the use of an analyzer program is optional. URL path components for 3270 display applications explains how to specify the URL path correctly when a URIMAP definition is used.End of change

CICS Web support does not provide support for partitions, logical devices codes, magnetic slot readers, outboard formatting, or other hardware features. You can use detectable fields with light pen support.