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 is running on a separate JVM or a separate run unit. It happens when the caller program used either the CALL CLIENT statement or the CALL RUN statement as well as when the current program was loaded from the 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.