Arguments

 

efn

   OpenVMS usage:ef_number
   type:         longword (unsigned)
   access:       read only
   mechanism:    by value
   Number of the event flag to be set when $SNDJBC completes. The
   efn argument is a longword containing this number; however,
   $SNDJBC uses only the low-order byte.

   When you queue the request, $SNDJBC clears the specified event
   flag (or event flag 0 if efn was not specified). Then, when the
   operation completes, $SNDJBC sets the specified event flag (or
   event flag 0).
 

func

   OpenVMS usage:function_code
   type:         word (unsigned)
   access:       read only
   mechanism:    by value
   Function code specifying the function that $SNDJBC is to perform.
   The func argument is a word containing this function code. The
   $SJCDEF macro defines the names of each function code.

   You can specify only one function code in a single call to
   $SNDJBC. Most function codes require or allow for additional
   information to be passed in the call. You pass this information
   by using the itmlst argument, which specifies a list of one or
   more item descriptors. Each item descriptor in turn specifies an
   item code, which modifies, restricts, or otherwise affects the
   action designated by the function code.
 

nullarg

   OpenVMS usage:null_arg
   type:         longword (unsigned)
   access:       read only
   mechanism:    by value
   Placeholding argument Reserved to VSI.
 

itmlst

   OpenVMS usage:item_list_3
   type:         longword (unsigned)
   access:       read only
   mechanism:    by reference
   Item list supplying information to be used in performing the
   function specified by the func argument. The itmlst argument is
   the address of the item list. The item list consists of one or
   more item descriptors, each of which specifies an item code. The
   item list is terminated by an item code of 0 or by a longword of
   0.

   To view the item code diagram and descriptor fields table, see
   the VSI OpenVMS System Services Reference Manual.
 

iosb

   OpenVMS usage:io_status_block
   type:         quadword (unsigned)
   access:       write only
   mechanism:    by reference
   I/O status block into which $SNDJBC writes the completion status
   after the requested operation has completed. The iosb argument is
   the address of the I/O status block.

   At request initiation, $SNDJBC sets the value of the quadword
   I/O status block to 0. When the requested operation completes,
   $SNDJBC writes a condition value in the first longword of the
   I/O status block. It writes the value 0 into the second longword;
   this longword is unused and reserved for future use.

   The condition values returned by $SNDJBC in the I/O status
   block are usually condition values from the JBC facility. These
   condition values are defined by the $JBCMSGDEF macro. In some
   cases, the condition value returned by $SNDJBC can be an error
   return from a system service or an OpenVMS RMS service that
   is used in executing the request. For the SJC$_SYNCHRONIZE_JOB
   request, the condition value returned is the completion status of
   the requested job.

   The condition values returned from the JBC facility are listed in
   the Condition Values Returned in the I/O Status Block section.

   Though this argument is optional, VSI strongly recommends that you
   specify it, for the following reasons:

   o  If you are using an event flag to signal the completion of
      the service, you can test the I/O status block for a condition
      value to be sure that the event flag was not set by an event
      other than service completion.

   o  If you are using the $SYNCH service to synchronize completion
      of the service, the I/O status block is a required argument
      for $SYNCH.

   o  The condition value returned in R0 and the condition value
      returned in the I/O status block provide information about
      different aspects of the call to the $SNDJBC service. The
      condition value returned in R0 gives you information about the
      success or failure of the service call itself; the condition
      value returned in the I/O status block gives you information
      about the success or failure of the service operation.
      Therefore, to accurately assess the success or failure of the
      call to $SNDJBC, you must check the condition values returned
      in both R0 and the I/O status block.
 

astadr

   OpenVMS usage:ast_procedure
   type:         procedure value
   access:       call without stack unwinding
   mechanism:    by reference
   AST service routine to be executed when $SNDJBC completes. The
   astadr argument is the address of this routine.

   If specified, the AST routine executes at the same access mode as
   the caller of $SNDJBC.
 

astprm

   OpenVMS usage:user_arg
   type:         longword (unsigned)
   access:       read only
   mechanism:    by value
   AST parameter to be passed to the AST service routine specified
   by the astadr argument. The astprm argument is this longword
   parameter.