Mounting the proc and devpts file systems

Mounting the proc and devpts file systems In order for certain programs to function properly, the proc and devpts file systems must be available within the chroot environment. Since kernel version 2.4 a file system can be mounted as many times and in as many places as you like, thus it's not a problem that these file systems are already mounted on your host system, especially so because they are virtual file systems. First make the mount points for these filesystems: mkdir -p $LFS/{proc,dev/pts} Now become root, since only root can mount file systems in unusual places. Then check again that the LFS environment variable is set correctly by running echo $LFS and making sure it shows the path to your LFS partition's mount point, which is /mnt/lfs if you followed our example. The proc file system is the process information pseudo file system through which the kernel provides information about the status of the system. Mount it with: mount proc $LFS/proc -t proc The devpts file system is now the most common way for pseudo terminals (PTYs) to be implemented. Mount it with: mount devpts $LFS/dev/pts -t devpts This last command might fail with an error to the effect of:

filesystem devpts not supported by kernel

The most likely cause for this is that your host system's kernel was compiled without support for the devpts file system. You can check which file systems your kernel supports by peeking into its internals with cat /proc/filesystems. If a file system type named devfs is listed there, then we'll be able to work around the problem by mounting the host's devfs file system on top of the new /dev structure which we'll create later on in the section on . If devfs was not listed, do not worry because there is yet a third way to get PTYs working inside the chroot environment. We'll cover this shortly in the aforementioned section. Remember, if for any reason you stop working on your LFS, and start again later, it's important to check that these file systems are mounted again before entering the chroot environment, otherwise some problems could occur.