USERDATA Data Source

The USERDATA data source indicates that a userdata string passed to the gateway may contain a value for a given data element. The USERDATA operand indicates either the relative position of the data element value, or identifies a keyword from which the appropriate value can be extracted.

In the relative position format, the USERDATA operand is specified as a decimal number. The token found in the userdata string at the zero-relative position is extracted and assigned to the data element. If the userdata string is null or contains fewer tokens than required, no value assignment is made. This format is frequently used when CL/SuperSession is operating in transparent mode, particularly when another logon solicitor is in use or when control is passed from one gateway to another. Data obtained from the logon solicitor or other VTAM® application may be conveniently passed to the gateway through a series of userdata tokens arranged in a predefined sequence.

In the keyword format, the USERDATA operand is specified as a character string that corresponds to a keyword occurring in the userdata string. When located, the value associated with the keyword is assigned to the data element. If the userdata string is null or does not contain the specified keyword, no value assignment is made. This format can provide a quick logon capability, bypassing the logon and application selection dialogs. If the user is able to satisfy all data element requirements by including the specified keywords in the logon userdata string, no additional prompting need occur.

In the first two data definition statements shown in the example below, the USERID and PASSWORD data elements may be supplied to the gateway as the first and second tokens occurring in the userdata string. If a userdata string is not furnished, both data elements must be acquired from other data sources.

The DEST statement illustrates the manner through which a keyword in the userdata string can be defined. If present, the value associated with the SENDTO keyword is assigned to the DEST data element. If a userdata string is not furnished, DEST must be acquired from another data source.

USERID        USERDATA(0)          USERID COMES FIRST
PASSWORD      USERDATA(1)          FOLLOWED BY PASSWORD
*
DEST          USERDATA('SENDTO')   EXTRACT  SENDTO=dest