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Questions tagged [checksum]

A checksum or hash sum is a fixed-size datum computed from an arbitrary block of digital data for the purpose of detecting accidental errors that may have been introduced during its transmission or storage. The integrity of the data can be checked at any later time by recomputing the checksum and comparing it with the stored one.

A checksum or hash sum is a fixed-size datum computed from an arbitrary block of digital data for the purpose of detecting accidental errors that may have been introduced during its transmission or storage.

The integrity of the data can be checked at any later time by recomputing the checksum and comparing it with the stored one. This process doesn't guarentee the data hasn't been corrupted, but is a good indication.

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mode 256 exaplin

I have this line in my code and I can't seem to understand how it works -(in order to find my problem) 0- (277 in HEX mode 256) I know the result should be 89 checksum = 0- (277(16) mode 256) but I don't remember why this is the C# byte[]…
David12123
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PrintWriter doesn't output all characters

public static void main(String[] args) throws FileNotFoundException { // Open file containing names with FileChooser dialog JFileChooser chooser = new JFileChooser( ); chooser.showOpenDialog(null); File fileObj =…
Laura Berrios
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what method can create a 16 byte checksum

I have a customer's broken application that I am trying to fix, but the original code has been lost, and I am trying to re-engineer it. It involves downloading 140 blocks of data, 768 bytes per block, to a device. In the data there is a "checksum"…
Sinbad
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C. Checksum calculation of array of ASCII hex values

i'm trying to calculate the checksum of an array of ASCII hex values. Say I have the following char exArray[] = "3030422320303030373830434441453141542355"; It's 20 pairs of hex values that each represent an ASCII character (eg. 0x41 = A). How can I…
Kater
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Update: How to address to an exact location in a PDF file?

Maybe this question seems a bit strange, but it has a very practical use case. Assume that we selected arbitrary a section of a PDF file to generate a checksum, such as the selected text (highlighted text) in the following screen shot: And then we…
Questioner
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Best way to check a file content is changed or not with perl?

There is a dynamic file which will be generated before my script executing. my $file = a.txt; Here i want to check: (Is content of $file changed)? Do_something: Skip; I'm looking for some solution as below: if ( if_modified( $file ); --> But We…
Hung Nguyen
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SVN checksum mismatch while migrating repository

after migrating our SVN repository from VisualSVN (Windows Server, SVN 1.7.7) to CentOS7 (SVN 1.7.14) we repeatingly (and each time for different files) get checksum errors when checking out from Eclipse or TortoiseSVN (Command line and GUI, all on…
user27772
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difficulty understanding checksum algorithm

I am examining a .d2s file using HxD, which lets me see the unencoded bytes of the file. The file is about 900+ bytes. Bytes 12 to 15 are a checksum. The algorithm for calculating the checksum is as follows: sum = (sum << 1) + data[i]; And here is…
dactyrafficle
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How to get artifact file's URI using Artifactory's checksum API where multiple artifacts have same SHA-1 / SHA-256 values aka file's content

Artifactory Version: 5.8.4 In Artifactory, files are stored in the internal database via file's checksum (SHA1) and for retrieval purposes, SHA-256 is useful (for verifying if file is intact). Read this first:…
AKS
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Checking for bit errors in a (USB) connection between two systems (for a game)

I'm doing a small project where I have two system communicating with each other. Here's a bit of information that might be useful for this question: The language I am using is C, and the game is PONG; I'm using freeRTOS on both systems. (sys1 and…
Stefan Horvath
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calculate checksum of hex data and send it by serial.to_bytes in python

I have this code: def checksum_calc(data): checksum = 0 for ch in data: checksum += ord(ch) return hex(checksum %…
Ali
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Calculating CRC-CCITT (Kermit) on two different sites, gives different results

I was playing around with CRC-CCITT (Kermit), and I noticed that when calculating the checksum on different sites, I got different results. On lammertbies.nl/comm/info/crc-calculation.html the result of 123456789 was 0x8921, but on crccalc.com it…
Josey
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3 character long checksum in HEX

I have just theoretical question. my and my buddy are arguing about existence of 3 character long checksum (0...F) (i.e. 1AB, 2C3 etc.). I am saying there is no known or commonly used algo/checksum but he does, it exist, but he does not know name.
Matheus555
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Checksum Based Storage Jfrog Artifactory

I have Jfrog Artifactory SAAS version installed in my org. In this I (admin though) donot have access to the server. I have been lately thinking on is it possible to have checksum based storage for artifactory on client side? If yes then what could…
Stack_IQ
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Computing MD5 checksums for files in a list

I'm working on a bit of a project in Python. I have a list of files that I want to get the md5checksums for. Then it stores the checksums in another list. Then it checks again and checks to see if they're different. I have the function for getting…
AustinM
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