Information saved during subroutine & function execution

During internal subroutine (and function) execution the following 
information is saved and restored upon return from the routine: 

   *  the status of DO loops and other structures 
   *  the <TRACE action 
   *  the <NUMERIC settings 
   *  the <ADDRESS settings 
   *  the <CONDITION traps 
      (CALL ON and <SIGNAL ON) 
   *  the <CONDITION information 
   *  the elapsed-time clocks 
      (function <TIME) 
   *  the <OPTIONS settings 
 

 Source:   IBM: OS/2 2.0 Procedures Language/2 Reference Manual