Where are all mount points stored in Linux

Question

I want to know where all mount points are stored; i.e. under any specific directory?

I want to be able to list all the existing mount points using a C Program. Which system call or function should I use?

Axolotl

#5071301 helpful? – Fillister

/etc/mtab holds the table with mounted filesystems. – Rinse

Answer 1

They are located in the /proc/mounts "file", which you can read and parse.

Renee

Since it in /proc directory, looks like it is not persistent in disk. So how it get stored when power is off? – Rafi

They're stored in /etc/fstab – Renee

Is /etc/fstab stored in a filesystem of partition? If yes, how does kenel find /etc/fstab during booting when no file system mounted? – Rafi

Yes it is. The kernel boot configuration stores which filesystem is to be mounted at / , When the / filesystem (that has to include atleast the basic /bin/ /etc /lib/ /sbin/ and similar) is mounted , /etc/fstab can be read to mount other filesystems. – Renee

So kernel boot configuation is stored in a specifial place like MBR or something, instead of file system? – Rafi

Almost. The MBR configuration does not have a lot of space, it just stores which disk/partition the actual configuration is stored on, so the next stage of the boot loader can read that configuration.(usually stuff in the /boot/ filesystem - which a boot loader can read before the kernel is even loaded. – Renee