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CPM OPERATING SYSTEMS/CPM 68K/1.0X SOURCES/v101/klib/chinit.c

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+/*****************************************************************************
+*
+*		     C C B   I N I T I A L I Z A T I O N
+*		     -----------------------------------
+*
+*	Routine "_chinit" is called from the run-time initialization to clear
+*	out all the CCB storage.
+*
+*	Calling sequence:
+*
+*		_chinit();
+*
+*****************************************************************************/
+#include	"stdio.h"			/* Include std definitions  */
+#include	"cpm.h"				/* Include CP/M definitions */
+FILE		 _iob[16];			/* Allocate CCB storage	    */
+_chinit()					/****************************/
+{						/*			    */
+	REG WORD	i;			/*	Index		    */
+	for(i=0;i<MAXFILE;i++)			/*	For all channels    */
+		__chinit(i);			/*	Init iob(i);	    */
+}						/****************************/
+
+/*****************************************************************************
+*
+*	The __chinit routine initializes only 1 channel.
+*
+*****************************************************************************/
+
+__chinit(i)
+{						/****************************/
+	REG FILE 	*ch;			/* -> CCB		    */
+	REG BYTE	*p;			/* Byte pointer temporary   */
+EXTERN	FILE		*_getc();		/* Converts fd to fp	    */
+	ch =  _getc(i);				/* Load address		    */
+	ch -> chan   = i;			/* Load channel byte	    */
+	ch -> flags  = 0;			/* clear flag word	    */
+	ch -> sector = -1;			/* Set no sector in buff    */
+	ch -> offset = 0;			/* Clear file offset word   */
+	ch -> hiwater = 0;			/* Init hiwater mark	    */
+	ch -> fcb.drive = 0;			/* Clear drive code	    */
+	p = &ch->fcb.fname[0];			/* Set to file var	    */
+	while (p< &ch->fcb.ftype[3])		/* Init file name fields    */
+		*p++ = ' ';			/* To spaces		    */
+	while (p < &ch->fcb.record)		/* Init rest of fcb	    */
+		*p++ = 0;			/* To zeros		    */
+}						/****************************/
+
+/*****************************************************************************
+*
+*	The _getc routine returns the address of a particular ccb.
+*
+*****************************************************************************/
+
+FILE *_getc(i)					/***************************/
+	REG  WORD	i;			/* input channel number    */
+{						/***************************/
+	extern	FILE  _iob[];			/* Declare external	   */
+	return(&_iob[i]);			/* Load addr, return	   */
+}						/***************************/