ptfun2_1() in ptfun2.ch is called 
Calling Ch function from C space: return value is 10
ptfun2_2() in ptfun2.ch is called 
Calling Ch function from C space: return value is 20
ptfun2_1() in ptfun2.ch is called 
retval of id1 = 10
ptfun2_2() in ptfun2.ch is called 
retval of id2 = 20
ptfun2_1() in ptfun2.ch is called 
retval of id2 = 10
