OPEN LINK command

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User 0, system administrator, system manager
The OPEN LINK command enables the link specified on the DEFINE LINK command.


OPEN LINK linkname


OPEN LINK newlinkname REPLACE oldlinkname

Where: linkname is the link specified on the DEFINE LINK command.

oldlinkname is a Horizon VTAM link that was abandoned using the CLOSE LINK command with the ABANDON keyword.

newlinkname is the name of the link to replace the abandoned Horizon VTAM link.

Usage notes

Depending on the TRANSPORT option of the DEFINE LINK command, the OPEN LINK command opens the CRAM channel or terminal connection. The OPEN LINK command also opens the SNA Communications Server ACB, the access method control block that SNA Communications Server uses to gather all information about the application program, which in this case is Model 204.

All system-wide control blocks and buffers necessary for activating sessions are allocated during open processing.

If the DEFINE LINK command specifies the PSWD parameter, the user is prompted for a password.

OPEN LINK must be issued before any TPROCESS, Transfer Control, or Horizon User Language statements are issued or before a Connect:connection is established.

Replacing an abandoned Horizon VTAM link

When a Horizon VTAM link has been abandoned, using the ABANDON keyword of the CLOSE LINK command, it is sometimes possible to open a new Horizon VTAM link to replace the abandoned link and to take over its associated REMOTE, SESSIONGROUP and PROCESSGROUP definitions, using the REPLACE keyword in the OPEN LINK command.

OPEN LINK newlinkname REPLACE oldlinkname

This is possible if the CLOSE LINK linkname ABANDON command left the old link in an abandoned state.

If, however, the CLOSE LINK command completed in such a way that the link can be re-opened, the following new message is produced:


In this case the keyword REPLACE of the OPEN LINK command cannot be used to replace the link. Instead the link should be re-opened as normal.