Re: Reading a file.

It certainly does not. You're doing something wrong or the input isn't what you think it is. ReadFile does no "translation".

If a file contains the the character "9" then the file will contain 0x39 or 0x39 0x00 depending on if it's stored as Unicode or not. ReadFile will return 0x39 regardless if you read a single byte.

In your example a character "9" does not get stored as the value 9 (i.e.0000 1001). If you want to get the value 9 back from it you have to read the character "9" and then use a conversion like _ttoi to get it to a numeric value.

-Chris



"ashishedn" <ashishedn@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message news:CA7247F3-89CA-4648-BF19-555C5AFAF367@xxxxxxxxxxxxxxxx
Problem is when i am reading a file through "readfile" function,it is being
read in character format.Suppose a value "9" is read,then it would get stored
in memory as "0x39" and i would be getting "0011 1001" instead of "0000 1001".
so the question is whether with "readfile" function a value could be read in
decimal format?

"Bruce Eitman [eMVP]" wrote:

You may have said something before, just not clear enough for the rest of to
understand what your problem is, and you still haven't done a very good job
of it.

Could it be that you saved the file with something like "%X", data? And so
now you need to convert it?

As I stated before: Then explain better what you expect and what is
actually happening.

--
Bruce Eitman (eMVP)
Senior Engineer
Bruce.Eitman AT EuroTech DOT com
My BLOG http://geekswithblogs.net/bruceeitman

EuroTech Inc.
www.EuroTech.com

"ashishedn" <ashishedn@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:50323539-6D7B-45E0-B096-7DAB20E80E65@xxxxxxxxxxxxxxxx
> That i have already tried.what is happening,if i fill data to the > buffer
> as
> integers then it is showing correct value.However,if data filled to the
> buffer is character values, then in memory ASCII values are displayed.
> But,for our main application, in both the cases(defining buffer as set > of
> integers/characters) ASCII values are coming.Therefore,i can't get > correct
> bitwise information as told earlier.
>
> "Bruce Eitman [eMVP]" wrote:
>
>> Huh?
>>
>> What is the problem? Reduce this a little, I suspect that it has >> nothing
>> to
>> do with "reading a file".
>>
>> What happens if you take a array and fill it with hard coded data, >> then
>> do
>> the operation? Doing so might help you understand what is going on, >> and
>> certainly would help me understand.
>>
>> Then explain better what you expect and what is actually happening.
>>
>> -- >> Bruce Eitman (eMVP)
>> Senior Engineer
>> Bruce.Eitman AT EuroTech DOT com
>> My BLOG http://geekswithblogs.net/bruceeitman
>>
>> EuroTech Inc.
>> www.EuroTech.com
>>
>> "ashishedn" <ashishedn@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
>> news:C59D4C87-F2BA-405A-AC4A-2FE26532C29D@xxxxxxxxxxxxxxxx
>> > Hi,
>> > I am trying to read data from a file to a buffer.Then, i want to >> > store
>> > bitwise information of a particular byte to a different array.
>> > Problem in doing so is, in memory, ASCII value of a character is
>> > getting
>> > stored and right shifting that value would't give the correct >> > bitwise
>> > information.
>> > Pl. help.
>> >
>> > Code written for that is.
>> >
>> > #include "stdafx.h"
>> >
>> > bool hw[4][8][8];
>> >
>> > int WINAPI WinMain( HINSTANCE hInstance,
>> > HINSTANCE hPrevInstance,
>> > LPTSTR lpCmdLine,
>> > int nCmdShow)
>> > {
>> > unsigned char inBuffer[256];
>> > unsigned char i,j,k;
>> > DWORD noofbytes = 0x00000001,nBytesRead;
>> > HANDLE hservice = CreateFile(L"\\hi.txt",GENERIC_READ,0,NULL,
>> > OPEN_EXISTING,0,NULL);
>> > DWORD d = GetLastError();
>> > if(hservice != INVALID_HANDLE_VALUE)
>> > {
>> > DWORD dwPtr = SetFilePointer(hservice,0x00,NULL,FILE_CURRENT);
>> > if(dwPtr == 0xFFFFFFFF)
>> > {
>> > printf("Pointer set error = %ul\n",GetLastError());
>> > // return 0;
>> > }
>> > else
>> > {
>> > BOOL bResult =
>> > ReadFile(hservice,&(inBuffer[i]),noofbytes,&nBytesRead,NULL);
>> > DWORD d = GetLastError();
>> > if(bResult && (nBytesRead == 0x01))
>> > printf("Read Value = %x\n",inBuffer[i]);
>> > else
>> > printf("Error in Reading = %ul\n",d);
>> > }
>> > }
>> > else
>> > printf("Error in opening the file = %ul",d);
>> > for(k=0;k<8;k++)
>> > {
>> > // printf("value of in Buffer = %d\n",inBuffer[j]);
>> > if(inBuffer[0]>>k & 0x01)
>> > hw[0][0][k] = TRUE;
>> > else
>> > hw[0][0][k] = FALSE;
>> > printf("Value of hw[0][0][%d] = %d\n",k,hw[0][0][k]);
>> > }
>> > return 0;
>> > }
>> >
>>
>>
>>




.

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