POSIX file I/O by Oliver Schmidt

git-svn-id: svn://svn.cc65.org/cc65/trunk@3457 b7a2c559-68d2-44c3-8de9-860c34a00d81

libsrc/apple2/close.s

@@ -0,0 +1,41 @@
+;
+; Oliver Schmidt, 30.12.2004
+;
+; int __fastcall__ close (int fd);
+;
+
+        .export 	_close
+
+        .import		closedirect, freebuffer
+        .import 	errnoexit, oserrexit
+        .import 	return0
+
+        .include	"filedes.inc"
+
+_close:
+        ; Process fd
+        jsr	getfd		; Returns A, Y and C
+        bcs	errno
+
+        ; Check for device
+        bmi	zerofd
+
+        ; Close file
+        jsr	closedirect	; Preserves Y
+        bcs	oserr
+
+        ; Mark fdtab slot as free
+zerofd: lda	#$00
+        sta	fdtab + FD::REF_NUM,y
+
+        ; Cleanup I/O buffer
+        jsr	freebuffer
+
+        ; Return success
+        jmp	return0
+
+        ; Return errno
+errno:  jmp	errnoexit
+
+        ; Return oserror
+oserr:  jmp	oserrexit