Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!rutgers!mcnc!beguine!Eliot.Henry
From: Eliot.Henry@samba.acs.unc.edu (BBS Account)
Newsgroups: comp.sys.mac.programmer
Subject: simple C Problem
Keywords: reading and writing to floppies
Message-ID: <1268@beguine.UUCP>
Date: 8 Oct 90 20:23:35 GMT
Sender: usenet@beguine.UUCP
Lines: 92


 I have a routine I wrote in pascal that reads and writes blocks from
a floppy drive. The problem is that when I converted it to C it doesn't
work. Yes, strange but true. It gives an error -50 every so often then
consistantly has trouble reading the next 65 or 66 sectors (there is a loop
that is writing to the entire disk) This is probably an embaressingly simple
problem. Any help would be greatly appreciated here is the code I have:


#include <stdio.h>
#include "DiskDvr.h"
 
 
 
main ()
 
 
{
 
 
 
OSErr			error;
ParamBlockRec	Param;
int				i,j,lb;
long int		buffersize=512;
char 			thebuffer[512];
 
 
/* This program will format an Apple Serial Hard Drive (SC20) */
/* Initialize Some Variables */
 
 
Param.ioParam.ioPosOffset=512;
Param.ioParam.ioPosMode=fsFromStart;
Param.ioParam.ioPermssn=fsRdPerm;
Param.ioParam.ioReqCount=buffersize;
Param.ioParam.ioBuffer=thebuffer;
Param.ioParam.ioRefNum=-5;
Param.ioParam.ioVRefNum=1;
 
printf ("\n");
 
error=PBRead(&Param,FALSE);
printf ("Read Error= %d\n",error);
printf ("Bytes Requested %d\n",Param.ioParam.ioReqCount);
printf ("Bytes Read %d \n",Param.ioParam.ioActCount);
 
/* Load the array with 0 bits (ascii character zero) */
for (i=1; i<=512; i++) 
	thebuffer[i]=0;
	
/* Write the 0 bits to the Drive */
 
printf ("Writing 0s....\n");
for (i=1; i<=800; i++)
{
	Param.ioParam.ioPosOffset=i*512;
	error=PBWrite (&Param,FALSE);
	if (error!=noErr) 
		printf ("Write Error:  %d\n",error);
	else
		printf ("Wrote sector: %d\n",i);
}
printf ("/n");
 
 
/* Verify the 0 bits */
 
printf("Verifying 0s...\n");
for (i=1; i<=800; i++)
{
	Param.ioParam.ioPosOffset=i*512;
	error=PBRead(&Param,FALSE);
	if (error!=noErr) 
		printf ("Read Error verifying sector %d\n",i);
	else
	{
		for (j=1; j<=512; j++);
			if (thebuffer[j]!=0) 
				printf ("Error in byte %d of sector %d\n",j,i);
			else
				printf (".");
	}
}
printf ("\n");
 
 
} /* END of the program */

Thanks in advance!

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