Table of Contents Previous Chapter Chapter 16: Fanout

Chapter 16: Fanout

1. Introduction

This record is used to trigger the processing of up to six other records. It has no associated device support.

2. Field Summary

--------------------------------------------------------------
Field  Type       DCT  Initial  Access  Modify  Rec Proc   PP   
                                                Monitor         
--------------------------------------------------------------
VAL    LONG       No   0        Yes     Yes     No         Yes  
SELM   RECCHOICE  Yes  0        Yes     Yes     No         No   
SELN   USHORT     No   1        Yes     Yes     No         No   
SELL   INLINK     Yes  0        No      No      N/A        No   
LNK1   FWDLINK    Yes  0        No      No      N/A        No   
LNK2   FWDLINK    Yes  0        No      No      N/A        No   
LNK3   FWDLINK    Yes  0        No      No      N/A        No   
LNK4   FWDLINK    Yes  0        No      No      N/A        No   
LNK5   FWDLINK    Yes  0        No      No      N/A        No   
LNK6   FWDLINK    Yes  0        No      No      N/A        No   
--------------------------------------------------------------

3. Field Descriptions

--------------------------------------------------------------------------------------------
Name           Summary            Description                                                 
--------------------------------------------------------------------------------------------
VAL            Value Field        This field exits only because every record type must have   
                                  a VAL field so that dNameToAddr succeeds when a field       
                                  name is not specified.                                      
SELM           Select Mechanism:  SELECT_ALL:   Select all links                              
                                  SELECTED:   Use SELN as index (1 to 6)                      
                                  MASK:   Use SELN as a mask to select an arbitrary           
                                  combination of links.                                       
SELN           Link Selection     If SELM=SELECT_ALL then this field is not used.             
                                  If SELM=SELECTED then this is the index (1 to 6) of the     
                                  link to select.                                             
                                  If SELM=MASK then this is the mask (in decimal) used to     
                                  determine the selected links.  For example, if SELN=1,      
                                  then LNK1 will be processed. If SELN=3 then  LNK1 and       
                                  LNK2 will be processed.  If SELN=63 then all links LNK1,    
                                  LNK2, ... LNK6 will be processed.                           
SELL           Link Selection     SELN is read from SELL.  SELL can be a constant, a          
               Location           database link, or a channel access link.                    
LNK1,...,LNK6  Link Selection     Link selection forward links are always processed in        
               Forward Links      numeric order.  That is LNK1 is always processed before     
                                  LNK2, LNK2 before LNK3, etc.                                
--------------------------------------------------------------------------------------------

4. Record Support Routines

init_record

This routine initializes SELN with the value of SELL, if SELL type is CONSTANT link, or creates a channel access link if SELL type is PV_LINK.

process

See next section.

5. Record Processing

Routine process implements the following algorithm:

  1. PACT is set to TRUE.
  2. The link selection SELN is fetched.
  3. Depending on the selection mechanism, the link selection forward links are processed. and UDF is set to FALSE.
  4. Check to see if monitors should be invoked.
  5. Scan forward link if necessary, set PACT FALSE, and return.
 
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