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