Mcen navaraj wrote:
> hi,
Hi, too.
> what is the difference between proc_register and
> create_proc_entry when creating an entry in
> the /proc.
can't explain like the experts.
i wrote something about proc in my reply to steve lustbader. check this here.
hope it brings you forward. i think it points into the correct directions.
about proc_register:
to steve, i wrote about this, too. i think now, i made a litte mistake.
proc_register meant a function called by you in init_module().
you write proc_register. in the proc_register function you implement calls like:
if a real proc_register exists and i turned wrong now, please correct me. (-:
--- start of a part
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/proc_fs.h>
int test_read_proc(char *buf, char **start, off_t off, int count, int *eof, void *data);
int test_write_proc(struct file *file, const char *buffer, unsigned long count, void *data);
struct proc_dir_entry *dir_entry, *fil_entry;
register_proc_files()
{
/* create directory */ /* &proc_root */
(struct proc_dir_entry*) dir_entry = proc_mkdir("test_dir", &proc_root);
/* create now a file */
(struct proc_dir_entry*) fil_entry = create_proc_entry("test_fil", dir_entry);
fil_entry->read_proc = test_read_proc;
fil_entry->write_proc = test_write_proc;
/*** this is closely like registering a device driver, isn't it ? ***/
}
unregister_proc_files()
{
/* remove files first */
remove_proc_entry("test_fil", dir_entry);
/* remove directory at NULL (register at proc_root) */
remove_proc_entry("test_dir", NULL);
}
int init_module(void)
{ register_proc_files(); }
void cleanup_module(void)
{ unregister_proc_files(); }
--- end of a part
i think this kind of pseudocode isn't insmodable. but explains how to.
about create_proc_entry(name, mode, parent)
creates a file with the name "name" in the proc dir.
"mode" ist the filemask for the creation.
"parent" is a pointer to a proc_dir_entry struct.
the func proc_mkdir creates a directory in the proc fs like shown above.
The struct proc_dir_entry contains function pointers to proc_read and proc_write.
And at last function pointers to get_info() and readlink_proc() for more /proc-ing.
the structure has some interesting attributes. find them out. i'll have to, too.
> when i try to use the proc_register in the program it
> shows error.I can able to compile the program
> but i cannot able to insmod the program.It shows
> unresolved symbol error.
Try to synchronize your code with my example.
Taken from a book. Tested in my third module.
Works great. And the read/write is implemented ;-).
> when i use the create_proc_entry it create an entry in
> the /proc directory.
try like in the example above.
add the rest of your code into the gaps :-).
> what is the difference in the /boot/System.map and
> /proc/ksyms ?
can't answer now. would like to know, too.
> Thanks
> bye
Edward.
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