Here are the detailed descriptions of the required
parameter group.
- User description information
- I/O; CHAR(*)
- Information about the user that the system uses as part of the auto-signon
process.
- Device description information
- I/O; CHAR(*)
- Information that the system uses to create or change the device that it
uses for this Telnet session.
- Connection description information
- I/O; CHAR(*)
- Information about the client connection that the exit program can use.
- Environment options
- INPUT; CHAR(*)
- An array containing all the RFC 4777 environment options negotiated by
the client. These are in the exact format that they were in when received
from the client and specified by RFC 4777. The array in general consists of
1 or more pairs of environment variable names and associated values. The RFC
specifies that each variable name is always be preceded by either an X'01'
or X'03' depending on whether it is an RFC 4777 defined VAR, or an application
specific defined USERVAR. If a value is associated with a VAR (or USERVAR),
that value will appear next in the array preceded by the RFC 1572 defined
VALUE character - X'01'. This sequence of VAR/VALUE pairs is repeated up to
a maximum of 1024 total bytes of negotiation data.
RFC 4777
and the more general Telnet negotiation RFCs also allow for control characters
to appear within the VAR/USERVAR variable names or their associated values.
This is allowed through the use of the ESC character X'02' and rules that
apply when the ESC character itself or Telnet IAC control characters must
appear in the negotiation sequence. Refer to RFC 1572 for a more complete
description of control character escaping rules.
While the environment
options buffer shows negotiations by the client, including passwords, Telnet
always overlays any clear-text or encrypted password values in the buffer
to avoid security exposures.
- Length of environment options
- The length of the environment options referenced in the preceding paragraph
is typically 1024 bytes. Because option negotiations are of undefined length,
any negotiations that exceed the length specified might be truncated to fit
in the environment options buffer.
- Allow connection
- OUTPUT; CHAR(1)
- Applies to all devices and indicates to the Telnet server whether all
devices should allow the client to connect to the Telnet server. If the device
type is display and you have enabled auto-signon, then this client might also
bypass the sign-on display on the system. The Valid values are as follows:
- 0
- Reject the request from the client
- 1
- Accept the request from the client
- Allow auto-signon
- OUTPUT; CHAR(1)
- Applies to DISPLAY device types, and indicates to the Telnet server whether
the auto-signon operation should be allowed to proceed for this particular
client. This parameter applies to display device types. If auto-signon is
allowed, then this client can bypass the sign-on device on the system. The
Valid values are as follows:
- 0
- Reject the application request from the client. The system ignores the
User profile, Current library, Program to call, Initial menu, and Device name
output parameters.
- 1
- Accept the application request from the client. The system may consider
the User profile, Current library, Program to call, Initial menu, and Device
name output parameters valid if the exit program returns them.