Questions tagged [recover]
recover.c, one of the assignments for Problem Set 4, will challenge you to search through the raw bytes of a camera's digital memory to recover a bunch of "deleted" JPEG images.
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i have a problem in p.set4 (recover)
can someone help me please ??
i have a problem in week 4 (recover)!!
i wrote my code and it was succesfully excuted
but when i used check 50
i have got errors which said that my images do not match ...
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Pset4- recover: recovered jpgs appear to be empty
I tried to implement recover through the simplest and shortest way I could imagine.
The code compiles and saves 50 JPGs with proper names, but when I open them, all of them are just empty and even ls -...
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CHECK50 Passes, but I Get 6/7 When Submitting
I've just completed pset4 - recover.
I did quite a bit of debugging and was finally able to pass all checkmarks with check50, style50 and Valgrind. After submitting I checked my grade and I received 6/...
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Recover PSET 4 Week 4 - skipping while loop
This is a follow up to my previous question. After I went through my code on debug50 it shows that my while on line 35 is not going through. I checked my code with other others on this site and they ...
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CS50 PSET 4 Recover - segmentation fault and blank file
I have been trying to solve this question for a while now but I am still not sure what is wrong. The program works fine before the while loop but after it stops working and when checking with check50 ...
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CS50 Recover Problem: Why does it give Segmentation fault (core dumped)
I have looked all over to see other people with issues with segmentation default on this problem. I don't see that i have the same issue and i am not sure what i did wrong
// Ensure proper command ...
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CS50 PSET4 Recover. Files created, images visible, why check50 fail?
Why isn't check50 clearing even though the files are created and the images are visible?
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
typedef uint8_t BYTE;
typedef ...
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program is free of memory errors
Im about to finish pset4, currently on recover! Everything is ok at the first look, program compiles, however, there is a problem when I run check50. As you can see from the title, something is off ...
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i am unable to open my cs50 card.raw file
#include <stdio.h>
#include <stdlib.h>
int main(int argc, char *argv[])
{
//open memory card
FILE *memorycard = fopen("card.raw","r");
if (memorycard =...
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program in recover pset4, please help me find the errors and if you could add how to debug the code, its will be helpful
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
typedef uint8_t BYTE;
int main(int argc, char *argv[])
{
if (argc != 2)
{
printf("./usage: recover filename\n");
...
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Recover, Produces 50 JPGS but doesn't pass check50 and the memory leak check is neutral (can't check)
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int check();
int main(int argc, char *argv[])
{
int name = 0;
FILE *fptr = NULL;
char filename[8]= {0};
int x = 0;
int i = ...
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in pset4, recover, why is the first jpg found treated differently from the other jpg files?
I'm starting to work on pset4, recover, and (as you can tell) things are not going well. I read posts from other students working on the same problem and realize some of them check for the jpg header ...
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pset 4: recover only recovers grey and black squares
I am unsure on why my code is only recovering black and grey squares, instead of images. I have tried closing the file img in multiple places, and I still can't seem to solve the problem, I believe it ...
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PSET4 Recover Successfully Generates Images But Does Not Match Correctly
Currently on PSET4 Recover. My code manages to generate 50 images which can be opened, however check50 states the images do not match correctly.
Would anyone be able to offer some advice?
#include <...
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pset4 recover segmentation fault (core dumped)
I am getting segmentation fault and i was searching on the internet, comparing with other codes, reading this forum, etc. and i still can not fix mine.
Explaining my code from the while:
read the ...
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Pset4 Recover getting segmentation fault but I have no idea why
This is the answer I have come up with for pset 4 recover:
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
int main(int argc, char *argv[])
{
// Ensure proper usage
...
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1
answer
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Why does the 0.49 jpg file doesn't match correctly?
I'm doint the recover PSET04. I think, I've done everything correct expect of the 0.49 jpg file. It says that it doesn't match correctly. And the last error in Check50 is "can't check until a ...
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Problem set 4 recover producing only one image, that too is corrupted
here is my code:
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
const int BLOCK_SIZE = 512;
int main(int argc, char *argv[])
{
// ensure ...
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Segmentation error in Recover Pset - any clues? A bit stumped
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "check_arguments.h"
#include "jpeg_file_structs_and_operations.h"
#include <stdio.h>
...
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PSET4 Recover - Why do I get Segmentation Error from Check50
my recover program compiles fine.
When I run the program, I do not get any errors. When I look at the 50 outfiles, I can see the pictures with the image preview.
Valgrind indicates that there are no ...
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P4 Recovers only first 512 bytes
im really struggling with this one and your help would be really appreciated
My code is working quite good but theres a error with writing file wich i cannot fix
// i will start with line where i ...
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pSet4: Recover Memory Leaking after opening a file
When I try to run my solution to recover in cs50 problem set 4, I get a segmentation fault. I tried to use check50, and I got a poor response for memory leaks.
:( program is free of memory errors
...
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CS50 pset4 recover Segmentation fault (core dumped) problem
I have already solved 2 errors from valgrind but cant solve the last 2 segmentation fault. Also how can i read the valgrind output efficiently. I just got lost between the text.
Thanks beforehand!
#...
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Recover runs, but leaks 472 bytes in 1 block
The code for recover (pset4) works fine, and has passed check50, except for the last check - no memory leaks. Valgrind shoots back:
==5482== Memcheck, a memory error detector
==5482== Copyright (C) ...
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Code for Good ol' Recover returns all fifty images (000-049), but doesn't pass Check50
I have gone through about 12 questions on the same issue - the code for recover works, but check50 isn't being kind:
:) recover.c exists.
:) recover.c compiles.
:) handles lack of forensic image
:) ...
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Pset 4 Recover finding 51 files
for recover my code returns 51 jpegs, was wondering where i went wrong? none of the jpegs seem viewable from vscode as well.
int main (int argc, char *argv[])
{
if (argc < 2|| argc <= 1)
{
...
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Why do the recovered images do not match (pset4 recover)
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
int main(int argc, char *argv[])
{ typedef uint8_t BYTE;
FILE *file = fopen(argv[1], "r");
int counter=0;
FILE *...
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PSET4 Recover segmentation fault
Good afternoon/morning,
I'm having problem with Problem set 4 Recover,
My code can compile but Segmentation fault (core dumped) keeps going out,
I checked on debug50 and it seems the segfault occurs ...
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Segmentation fault in pset4 recover when reading file
I tried solving recover.c. But when I tried to run it (without valgrind), I got segmentation fault. When I ran it again with valgrind, it told me that the culprit is in line 40, where I read the file ...
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Hello guys... Good day. I'm currently on the pset 4 (recover). program is working well, but the (valgrind) requirement in the check50 isn't checking
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
typedef uint8_t BYTE;
int main(int argc, char *argv[])
{
// Check that command-line arguments is 2
if (argc != 2)
...
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Getting segmenatation fault even though i freed memory
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
typedef uint8_t BYTE;
int main(int argc, char *argv[])
{
// Only allow 2 command line arguments
if (argc != 2)
...
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answer
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PSET 4 Recover Valgrind Check
Valgrind indicates I have 49 memory blocks left to close. Otherwise, the code satisfies check50. I'm thinking I need to nest the fclose functions within the loop, but I can't get it right. Thoughts?
...
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Pset 4: Why Error at end of checkcs50?
this is how my code looks. Only *filename has a malloc attached to it.
Why this valgrind error.
This is how the logs look.
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Memory leak in Recover (PSet4)
I'm working on Recover and it all works fine but I've got a memory leak I don't know how to get rid of. My code is this:
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
...
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CS50 Problem Set 4 - Recover, fclose undeclared identifier issue
My first time posting on the forum so hope someone can help. I've been scratching my head over this code for a while now and can't understand why I get the undeclared identifier! My code seems to ...
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CS50x pset 4 - Recover = correct code, no jpegs?
I've been working on CS50x pset 4 - Recovery and check50 is saying that I have done everything correctly. The problem is that I don't see any jpgs in the folder. What do I seem to be doing wrong?
#...
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PSET 4 Recover I am not getting all the checks in my program
The program works fine but the last condition is not fulfilled. Valgrind tests failed. I know I have to close the opened files but I cant seem to figure out where to do that. Please help.
Following is ...
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RECOVER, can't see images
I've been working on recover for days now.
I've been able to solve the segmentation fault issues and the code compiles and creates all 50 jpg files, but doesn't write the files correctly. I played ...
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My recover program makes all 50 jpegs without errors or segmentation faults. However I only recover the first image correctly. What am I missing?
I can make the file without error. When I run the code all 50 jpeg files are created. When I check the images only the first one appears and the rest say error while loading. When I run check50 I get ...
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I set up Recover with buffer files, but I'm not sure where the image is being sent to, are we rewriting the original card.raw file? I'm confused
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
//number of bytes in jpeg file
const int BLOCK_SIZE = 512;
int main(int argc, char *argv[])
{
//ensure proper use
if(argc !=...
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1
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CS50 PSET 4 Recover Segmentation fault (core dumped)
I am working on PSET4 Recover from the CS50 course, but I can't seem to get it to work. I keep getting segmentation fault (core dumped). I've tried changing my code many times, but keep the ...
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Understanding Pset4 Recover Valgrind Errors
My code for Recover is passing all the tests in Check50 except for the final one on memory errors. When I run valgrind ./recover I get this:
When I look into the details of why I'm not passing ...
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In recover, image files are not writing bytes correctly. Why?
All 49 images are written but they don't have the accurate data. I can't find where I made the mistake. Here's my code:
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
// ...
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Pset4 Recover, only getting first block of data written to image file
I have trawled through previous posts for hours trying to find a solution, but I can not seem to find anything similar. If I have missed it, then apologies!
The code is recovering/opening all 50 image ...
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In pset4 recover, do I need to loop 512 bytes to make it work?
Here's my code:
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
// Function headers
int fsize(FILE *fp);
int main(int argc, char *argv[])
{
// Check the validity of ...
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CS50 PSET 4 RECOVER WORKING BUT NOT PASSING CS50 - SEGMENTATION FAULT
This is for CS50 PSET 4 recover.
I am struggling with identifying the segmentation fault that check50 shows. Upon running, it seems to generate the 50 images correctly without error, and valgrind does ...
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PSET4 - Recover - set output file pointer to NULL
case 1:
FILE *file_out = NULL;
case 2:
FILE *file_out;
"file_out" is a newly defined file pointer to where the recovered JPEG blocks will be written to. I tried both case 1 and case 2 and ...
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Pset4 (cs50) fails check50 (segmentation fault)
Here's my code :
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
typedef uint8_t BYTE;
int main(int argc, char *argv[])
{
if (argc != 2)
{
printf("./...
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1
answer
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pset4 recover: segmentation fault when closing file
I have been stuck with this segmentation fault for quite a while now. After running valgrind I was able to determine that it happens when I close the output file at the end of the code, but I have no ...
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pset4 recover not working due to segmentation fault
I have come up with this code for recover but there is a segmentation fault I can't figure out where. any pointers welcome.
BYTE buffer[512];
int i = 0;
FILE *jpeg = NULL;
while (fread(...
