Arguments

 

msgbuf

   OpenVMS usage:char_string
   type:         character-coded text string
   access:       read only
   mechanism:    by descriptor-fixed-length string descriptor
   User buffer specifying the operation to be performed and the
   information needed to perform that operation. The msgbuf argument
   is the address of a character string descriptor pointing to the
   buffer.

   The format and contents of the buffer vary with the requested
   operation; however, the first byte in any buffer is the request
   code, which specifies the operation to be performed. The $OPCMSG
   macro defines the symbolic names for these request codes.

   The following table shows each operation that $SNDOPR performs
   and the request code that specifies that operation:

   Request Code   Corresponding Operation

   OPC$_RQ_       Sends a user cancellation request to specified
   CANCEL         operator terminals. You use this request code
                  to notify one or more operators that a previous
                  request is to be canceled. To specify OPC$_RQ_
                  CANCEL, you must also specify the chan argument.

   OPC$_RQ_LOGI   Initializes the operator log file.

   OPC$_RQ_       Sends an operator reply to a user who has made a
   REPLY          request. Operators use this request code to report
                  the status of a user request. The format of the
                  message buffer for this request is the format
                  of the reply found in the user's mailbox after
                  the call to $SNDOPR completes. All functions of
                  $SNDOPR that deliver a reply to a mailbox do so in
                  the format described for this request code.

   OPC$_RQ_RQST   Sends a user request to operator terminals. This
                  request code is used to make an operator request.
                  If you specify a reply to the request (by using
                  the chan argument), the operator request is kept
                  active until the operator responds.

   OPC$_RQ_       Reports the status of an operator terminal.
   STATUS         Operators use this request to display the operator
                  classes for which the specified terminal is
                  enabled and a list of outstanding requests.

   OPC$_RQ_       Enables an operator terminal. You use this request
   TERME          to enable a specified terminal to receive operator
                  messages.

   Refer to the VSI OpenVMS System Services Reference Manual to
   view the diagrams depicting the message buffer for each of these
   request codes.
 

chan

   OpenVMS usage:channel
   type:         word (unsigned)
   access:       read only
   mechanism:    by value
   Channel assigned to the mailbox to which the reply is to be sent.
   The chan argument is a longword value containing the number of
   the channel. If you do not specify chan or specify it as the
   value 0 (the default), no reply is sent.

   If a reply from the operator is desired, you must specify the
   chan argument.