copy_to_user not working in kernel module

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http://stackoverflow.com – I was trying to use copy_to_user in kernel module read function, but am not able to copy the data from kernel to user buffer. Please can anyone tell me if I am doing some mistake. My kernel version is 2.6.35. I am giving the portion of kernel module as well as the application being used to test it. Right now my focus is why this copy_to_user is not working. Any help will great. ///////////////////////////////////kernel module////////////////////////////////////// #define BUF_LEN 80 static char msg[BUF_LEN]; static char *msg_Ptr; static int device_open(struct inode *inode, struct fil (HowTos)