isCOBOL Evolve : Appendices : Library Routines : C$CALLEDBY
C$CALLEDBY
The C$CALLEDBY library routine returns the name of the program that has called the currently running program.
Syntax:
 CALL "C$CALLEDBY" USING  callingProgram
                   GIVING returnCode
Parameters:
callingProgram
PIC X(n)
Receives the name of the caller.
Return code:
returnCode can be any signed numeric data item and provides additional information:
1
The currently running program has been called by another isCOBOL program.
0
The caller program name couldn’t be retrieved. Possible causes are:
• The current program is the main program, the one started on the command line
• The caller program is either a Java class or a C function, not a COBOL program
• The current program was loaded from iscobol.remote.code_prefix
• The caller program has a CLASS-ID instead of a PROGRAM-ID.
-1
Missing or invalid parameter.
Examples:
Example - Display what program called the current one in the beginning of the program
working-storage section.
77 calling-prg  pic x(256). 
...
procedure division.
main.
  call "c$calledby" using calling-prg
  if calling-prg = spaces
     display message "No program called me"
  else
     display message "I was called by program : " calling-prg
  end-if.