Hello,

I have an embedded linux kit where I can plug in a USB Flash Drive.

The USB Flash Drive has multiple folders, sub-folders and files.

I would like to create some C code to copy these folders and files from the mass storage device to the file system on my kit.

I would want to do this somewhat in multiple copies so I could check to see if there was still room in the file system I am copying to.

Any ideas as to how to go about this would be greatly appreciated.

You can use the rename(2) function, or you can fork() and exec() and perform a shell mv call.

I've done both, but prefer using the mv method.

I found the following and was trying to use it. Unfortunately it does not keep keep the directory structure on the USB drive intact when copying over.

For example if I tried the following: Copy(/media/sda1/foo/foo.txt, "/home/Usb_Files");

I see foo.txt at /home/Usb_Files/foo.txt instead of /home/Usb_Files/foo/foo.txt

Any idea on how to do this?

I am really stuck.


int Copy(char *source, char *dest)
{
int childExitStatus;
pid_t pid;
int status;
if (!source || !dest) {
/* handle as you wish */
}

pid = fork();

if (pid == 0) { /* child */
execl("/bin/cp", "/bin/cp", "-R", source, dest, (char *)0);
}
else if (pid < 0) {
/* error - couldn't start process - you decide how to handle */
}
else {
/* parent - wait for child - this has all error handling, you
* could just call wait() as long as you are only expecting to
* have one child process at a time.
*/
pid_t ws = waitpid( pid, &childExitStatus, WNOHANG);
if (ws == -1)
{ /* error - handle as you wish */
}

if( WIFEXITED(childExitStatus)) /* exit code in childExitStatus */
{
status = WEXITSTATUS(childExitStatus); /* zero is normal exit */
/* handle non-zero as you wish */
}
else if (WIFSIGNALED(childExitStatus)) /* killed */
{
}
else if (WIFSTOPPED(childExitStatus)) /* stopped */
{
}
}
}

Also if I try Copy(/media/sda1/foo/foo.txt, "/home/Usb_Files/foo");

It says the cp cannot stat no such file or directory

Any help would be greatly appreciated.

You have to create the foo destination directory first, then copy foo.txt into it

In a more refined program, you could check if destination directory exists before atempting to copy a file into it

[edit]

or use -p option for mkdir

man mkdir