External Symbol Dictionary (ESD)

The listing opposite shows an ESD which includes an external reference, in this case to IEFBR14

The process of resolving external references is achieved by AUTOCALL control statements which instruct the binder to resolve external references against a specified library. Whilst AUTOCALL and LIBRARY control statements are optional, automatic library call requires that there is a SYSLIB DD, otherwise a severity 8 error is issued, i.e. the Linkage Editor terminates COND CODE 0008.

The AUTOCALL feature can be disabled with the NCAL option.

Resolving External References (2 of 2)

                                    External Symbol Dictionary   
Symbol   Type   Id     Address  Length   Owner Id Flags Alias-   
ESD2      SD 00000001 00000000 0000007C             02           
IEFBR14   ER 00000002                                        

  Active Usings: None                                            
  Loc  Object Code    Addr1 Addr2  Stmt   Source Statement       
000000                00000 0007C     1 ESD2     CSECT           
                                      2 ESD2     AMODE 31        
                                      3 ESD2     RMODE 24        
                                      4          PRINT NOGEN     
000000                00000 0007C     5 ESD2     CSECT           
                 R:F  00000           6          USING *,R15     
000000 47F0 F058            00058     7 BEGIN    B     START

At the end of input processing the binder performs final AUTOCALL, where libraries specified on LIBRARY control statements and the SYSLIB DD are used to resolve any remaining external references. External references that are unresolved at the end of final auto-call are treated as severity 8 errors, i.e. the Linkage Editor terminates COND CODE 0008.