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CONTRIBUTIONS/cpm-handbook/cpmsrc/FIG5-20.ASM

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+; Figure 5-20
+;
+;	CF
+;	Create File
+;	This subroutine creates a file. It erases any previous
+;	File before creating the new one.
+;
+;	Entry Parameters
+;
+;		DE -> File Control Block for new file
+;
+;	Exit Parameters
+;
+;		Carry Clear if operation successful (A = 0,1,2,3)
+;		Carry Set if error (A = 0FFH)
+;
+;	Calling Sequence
+;
+;		LXI	D,FCB
+;		CALL	CF
+;		JC	ERROR
+;
+B$ERASE		EQU	19	;Erase File
+B$CREATE	EQU	22	;Create File
+BDOS		EQU	5	;BDOS Entry Point
+;
+;
+CF:
+	PUSH	D		;Preserve FCB Pointer
+	MVI	C,B$ERASE	;Erase any existing file
+	CALL	BDOS
+	POP	D		;Recover FCB Pointer
+	MVI	C,B$CREATE	;Create (and open new file)
+	CALL	BDOS
+	CPI	0FFH		;Carry set if OK, Clear if Error
+	CMC			;Complete to use Carry set if Error
+	RET
+