sysVar system variable (web transaction fields)

The sysVar system variable holds miscellaneous values that do not fit in other libraries.

For core sysVar variables, see EGL library sysLib.

EGL supplies two unique identifiers that you can use as keys when saving program state during a web transaction session:
  • A session ID is a unique string specific to a web application server session. EGL saves this string in the sysVar.sessionID system variable (see sessionID considerations for web transactions). This session ID is created automatically. It is also possible to start a session ID manager manually. For more information, see Gateway servlet parameters.
  • A conversation ID is specific to an execution thread that runs a sequence of program proxies in a given web application server session. EGL stores the conversation ID is stored in sysVar.conversationID; see conversationID.

    For COBOL programs, the primary purpose of the session ID and conversation ID is to synchronize information between tiers 2 and 3.

The qualifier sysVar can precede the name of each EGL system variable listed in the following table:

Table 1. Web transaction sysVar system variables
System variable Description
conversationID Stores the conversation ID that is assigned when an EGL program uses a VGUI record to present a web page.
sessionID considerations for web transactions Contains an ID that is specific to the web application server session.