Question

While traversing from my current path , and searching for a file , I’m having problems locating the file .

I suspect the that the path is the blame for that due to chdir , in the next code :

The associated folders are :

• 12,13,14 , 12 is father directory
• 13 inside 12 , 14 inside 13
• david1.txt inside 14
• get_current_dir_name() is a Linux function , not mine

I run the executable file from Desktop , like this (here are printf-s for trying to locating the problem) :

    // doesn't work 

   a@ubuntu:~/Desktop$ ./exer4 12 david1.txt

    Current path is :12

    Current path is :/home/a/Desktop/12/13

    Current path is :/home/a/Desktop/12/13/14

//////////////////////////////////////////////////
    // doesn't work      

    a@ubuntu:~/Desktop$ ./exer4 12/13 david1.txt

    Current path is :12/13

    Current path is :/home/a/Desktop/12/13/14

////////////////////////////////////////////////
    // doesn't work 

    a@ubuntu:~/Desktop$ ./exer4 12/13/14 david1.txt

    Current path is :12/13/14

If I remove these lines :

chdir(path);                          // the problem is probably here 
strcpy(path, get_current_dir_name()); // and here 

Then every query that involves only a single library name – works , for example :

// works : 

a@ubuntu:~/Desktop$ ./exer4 12 david1.txt

Current path is :12

Current path is :12/13

File found!

12/13/14/david1.txt-rw-rw-r-- 1 1000 1000 0 2012-06-17 08:10 

Current path is :12/13/14
////////////////////////////////////////////////////////////
// works 
a@ubuntu:~/Desktop$ ./exer4 12/13 david1.txt

Current path is :12/13

File found!

12/13/14/david1.txt-rw-rw-r-- 1 1000 1000 0 2012-06-17 08:10 

Current path is :12/13/14

////////////////////////////////////////////////////////////
// Doesn't work
a@ubuntu:~/Desktop$ ./exer4 12/13/14 david1.txt

Current path is :12/13/14

Any idea what I’m doing wrong here ? I’ve tried to change countless times but nothing fixed it . Thanks

Answer 1

When doing strcpy(path, get_current_dir_name()), you don’t check that the buffer isn’t exceeded.
If path is argv[1], you’re overrunning the stack.
My guess is that you overrun the file name (argv[2]), and then you start looking for the wrong name (and don’t find it).