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COUPLE                                                   CP Privilege Class:  G

Use the COUPLE command to connect your virtual nondedicated channel-to-channel
device adapter (CTCA) to another user's virtual channel-to-channel adapter,
or to another one of your own virtual channel-to-channel adapters.  The format
of the COUPLE command is:
+----------+------------------------------------------------------------------+
| COUPLE   | vaddr1 [To] userid [vaddr2]                                      |
+----------+------------------------------------------------------------------+
where:

vaddr1   is the virtual address (cuu) of your channel-to-channel adapter.

[To] userid
         is the user identification of the virtual machine to which vaddr1 is
         to be connected.  If vaddr1 is to be connected to your own virtual
         machine, userid may be specified as an asterisk (*).  The user must be
         logged on and have a virtual channel-to-channel adapter defined.  If
         the keyword TO is omitted, the userid cannot be "T" or "TO."

vaddr2   is the virtual address (cuu) of the channel-to-channel adapter to be
         connected to vaddr1.


Responses

CTCA vaddr1 COUPLE TO userid vaddr2
   This is the response you receive when you issue the COUPLE command.
   vaddr1   is the address of your channel-to-channel adapter.
   userid   is the identification of the receiving virtual machine.
   vaddr2   is the address of the channel-to-channel adapter of the receiving
            user (or a different channel-to-channel adapter in your own virtual
            machine).

CTCA vaddr2 COUPLE BY userid vaddr1
   This is the response that the user specified by userid receives when you
   issue the COUPLE command.
   vaddr2   is the address of the channel-to-channel adapter of the receiving
            user.
   userid   is the identification of the user who issued the COUPLE command.
   vaddr1   is the address of the issuing user's channel-to-channel adapter.

CTCA vaddr1 DROP FROM userid vaddr2
   This is the response that the user who issued the COUPLE command receives if
   the virtual CTCA vaddr1 was already coupled when the COUPLE command was
   issued.  The previous connection is terminated.  This response is always
   followed by the response:
   CTCA vaddr1 COUPLE TO userid vaddr2