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GeneralRe: Check existance of directory Pin
Joel Lucsy31-Jul-03 7:31
Joel Lucsy31-Jul-03 7:31 
GeneralRe: Check existance of directory Pin
Toni7831-Jul-03 18:55
Toni7831-Jul-03 18:55 
GeneralRe: Check existance of directory Pin
HPSI31-Jul-03 20:14
HPSI31-Jul-03 20:14 
QuestionUnder what circumstances does IE run in explorer.exe process? Pin
Tommy Svensson31-Jul-03 3:57
Tommy Svensson31-Jul-03 3:57 
AnswerRe: Under what circumstances does IE run in explorer.exe process? Pin
Mike Dimmick31-Jul-03 4:56
Mike Dimmick31-Jul-03 4:56 
GeneralRe: Under what circumstances does IE run in explorer.exe process? Pin
Tommy Svensson31-Jul-03 5:04
Tommy Svensson31-Jul-03 5:04 
Generaldialog in top left of screen Pin
si_6931-Jul-03 3:43
si_6931-Jul-03 3:43 
GeneralRe: dialog in top left of screen Pin
si_6931-Jul-03 3:45
si_6931-Jul-03 3:45 
GeneralRe: dialog in top left of screen Pin
User 665831-Jul-03 4:01
User 665831-Jul-03 4:01 
GeneralRe: dialog in top left of screen Pin
si_6931-Jul-03 5:19
si_6931-Jul-03 5:19 
Generaldrag 'n drop CBitmap Pin
selena31-Jul-03 3:29
selena31-Jul-03 3:29 
GeneralComponent oriented application Pin
Jerome Conus31-Jul-03 3:25
Jerome Conus31-Jul-03 3:25 
GeneralRe: Component oriented application Pin
armentage31-Jul-03 4:00
armentage31-Jul-03 4:00 
GeneralRe: Component oriented application Pin
Jim Crafton31-Jul-03 8:06
Jim Crafton31-Jul-03 8:06 
GeneralMFC Tree View Pin
rahulmsaxena31-Jul-03 3:24
rahulmsaxena31-Jul-03 3:24 
GeneralRe: MFC Tree View Pin
Tim Ranker31-Jul-03 3:39
Tim Ranker31-Jul-03 3:39 
GeneralRe: MFC Tree View Pin
rahulmsaxena31-Jul-03 3:51
rahulmsaxena31-Jul-03 3:51 
GeneralRe: MFC Tree View Pin
Tim Ranker31-Jul-03 4:54
Tim Ranker31-Jul-03 4:54 
GeneralRe: MFC Tree View Pin
rahulmsaxena31-Jul-03 9:20
rahulmsaxena31-Jul-03 9:20 
GeneralRe: MFC Tree View Pin
Tim Ranker31-Jul-03 10:16
Tim Ranker31-Jul-03 10:16 
GeneralHowto: get a Two's Complement Checksum Pin
DudleyDoorite31-Jul-03 2:43
DudleyDoorite31-Jul-03 2:43 
GeneralRe: Howto: get a Two's Complement Checksum Pin
Ryan Binns31-Jul-03 3:19
Ryan Binns31-Jul-03 3:19 
GeneralRe: Howto: get a Two's Complement Checksum Pin
Tim Ranker31-Jul-03 3:31
Tim Ranker31-Jul-03 3:31 
Hello Dudley,

It is perfectly acceptable to have the sum of all the bytes "roll over" beyoung the maximum value of the data type you are using, 8 bit or byte. If your running checksum is a byte something like the following will probably happen:

Lets say you want to add the following three bytes 127, 63, and 98. The running 8 bit checksum and 16 bit check sum would be the following.

                Checksum Total
Byte         (8 bit)       (16 bit)
127(0x7F)   127(0x7F)     127(0x7F)
63(0x3F)    190(0xBE)     190(0xBE)
98(0x62)     32(0x20)     288(0x0120)

The 8 bit check sum is just the 8 LSB or the 16 bit checksum.
In your implementation, you can just use a BYTE for your checksum and add all the data bytes, or you can use a larger data type like an int for your checksum and your 8 bit checksum would be the 8 Least Significant Bits.

Don't forget that after you have added all the bytes you need to do the 2's complement.
Invert all the bits and add one.

(C language)
checksum = ~checksum + 1;

The final checksum for the above example would be:
224(0xE0)

When you add the sum of all the bytes and the final checksum together, you should get zero.
32(0x20) + 224(0xE0) = 256(0x100);
But 256 is really 0 for a 8 bit data type (0x00);

Hope this helps.
Tim
GeneralRe: Howto: get a Two's Complement Checksum Pin
DudleyDoorite31-Jul-03 3:43
DudleyDoorite31-Jul-03 3:43 
GeneralExtracting Audio from AVI Pin
Anonymous31-Jul-03 2:22
Anonymous31-Jul-03 2:22 

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