PCmtScan FSM

PCmtScan(&PState):

Pstate: r == InCode?

InCode r=ScanCode(fp)

Pstate: r == InCmt?

InCmt r=ScanCmt(fp)

PASS

(with action slots)

Initialize:

PState=inCode

Pstate: r == EndFile?

EndFile printf(“\nEnd

of Input\n”)

Pstate: r==Error|default

other printErrMsg(PState);

close(fp);

FAIL

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Notes:

PState = InCode;

while (1) {

//exit iff (PState == EndFile || PState == Error)

// fprintf(stdout, "%cPState = %d%c",LF,PState,LF);

switch((int)PState){

case InCode:{PState = ScanCode(fp); break;}

case InCmt: {PState = ScanComment(fp); break;};

case EndFile:{fprintf(stdout,

"\nEnd of Input; PState = %d;\n", PState);

exit(1);

}

case Error:

default:{

PState = Error;

fprintf(stderr,

"\nError:Invalid PState = %d\n", PState);

exit(1);

};

}; // end switch(PState)

}; // end while