lkml.org 
[lkml]   [2000]   [Jul]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: Printing the messages through printk while using Xwindows.
before people blame me for corrupting their filesystems, here is a hint:

registering a filesystem doesn't give you moral right to attempt to mount
it :)

seriously though, FS_SINGLE filesystems must be kern_mount()'d before they
can be user-mounted so if you try to usermount the filesystem below you
will get an oops for a well-known reason (nothing to do with terminals or
X :) (and after the oops you won't be able to umount any filesystems so
fsck will be inevitable)

Regards,
Tigran

On Fri, 28 Jul 2000, Tigran Aivazian wrote:

> On Fri, 28 Jul 2000, Russell King wrote:
> > Therefore, its fine if you've got one of the few cards that fbcon
> > works with. Otherwise you're using vgacon, and it doesn't work.
>
> It does actually work on plain vga without any fb support at all. Try it
> and see. Here is a little ready-to-compile module for you to try.
>
> Regards,
> Tigran
>
> #define __KERNEL__
> #define MODULE
>
> #include <linux/module.h>
> #include <linux/init.h>
> #include <linux/sched.h>
>
> print_string(char *str)
> {
> struct tty_struct *tty = current->tty;
>
> (*tty->driver.write)(tty, 0, str, strlen(str));
> (*tty->driver.write)(tty, 0, "\015\012", 2);
> }
>
>
> static struct super_block *
> single_read_super(struct super_block *s, void *data, int silent)
> {
> char buf[100];
> sprintf(buf, "comm=%s\n", current->comm);
> print_string(buf);
> return NULL;
> }
>
> static DECLARE_FSTYPE(single_fs_type, "single", single_read_super, FS_SINGLE);
>
> static int __init init_single_fs(void)
> {
> char buf[100];
> int ret = register_filesystem(&single_fs_type);
>
> printk(KERN_ERR "init_single_fs(): ret = %d\n", ret);
> sprintf(buf, "comm=%s\n", current->comm);
> print_string(buf);
> return ret;
> }
>
> static void __exit exit_single_fs(void)
> {
> char buf[100];
> sprintf(buf, "comm=%s\n", current->comm);
> print_string(buf);
> unregister_filesystem(&single_fs_type);
> }
>
> module_init(init_single_fs);
> module_exit(exit_single_fs);
>
>


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:57    [from the cache]
©2003-2011 Jasper Spaans