command that copies count block of the bs size from the if to of file | dd if=input_file of=output_file count=1 bs=128
if count is not specified it copies to EOF |
What is I-node? | It is a structure that stores all information about a file except its name and data |
command that displays all information on a file stored in its i-node structure | stat file_name |
How are files identified in a file system?
How are directories indetified in a file system? | i-numbers
not names!!!
Directories:
(name, i-number) |
command that lists i-numbers of files and dirs | ls -i |
Can numerous names be associated with the same i-node? | Yes, such names are called hard links |
What are time stamps? | records of times in which specific actions were performed |
How regular file is denoted?
How directory is denoted?
How symbolic link is denoted? | -
d
l |
What are block devices? | allow for random buffered access to devices |
What are character devices? | allow for sequential unbuffered access to devices
Examples:
/dev/null
/dev/random
/dev/zero |
command for listing block devices | lsblk |
Which files are considered to be hidden? | The ones which start with a dot
special wildcard for hidden files: .* |
Does rm skip hidden files? | Yes it does
rm * -deletes all files except hidden ones
rom * .* -deletes all the files |
command that displays directory content size recursively | du [options] dir_name
du -s -summarized value
du -h -human readable |
lists all files that are currently open | lsof
lsof some_file -displays info on a selected file |
command that copies count block of the bs size from the if to of file | dd if=input_file of=output_file count=1 bs=128
if count is not specified it copies to EOF |
Which file system is assumed by most linux distros? | ext4 |
What is disk partitioning> | Disk Partitioning is the process of dividing a disk into one or more logical areas, often known as partitions, on which the user can work separately. |
How many file systems are created in linux systems?
What about BSD or Solaris? | One file system per partition is created contrary to BSD and Solaris |
command used for disk partition management | fdisk
requires root privilages |
command for creating a file system | mkfs -t type device
mkfs.type -alternative notation |
What does mounting file system mean? | By mounting we attach file system to existing file systems. They are seen as branches of tree like hierarchal structure |
How many file systems can be mounted as a top-level file system? | Only one
its name is root file system |
Can parent and child file systems be of different types? | Yes they can |
What happens to a directory that is used as a mount point? | If its not empty its contests become inaccessible |
What are pseudo mounted files? | Addresess places i guess |
command used for pounting file systems | mount -t type -o options device mountpoint |
How to unmount a file system? | umount device|mountpoint |
Can we mount several file systems to one mount point at the same time? | Yes |
command that displays disk size usage for all mounted file systems | df |
command that checks and repairs systems | fsck |
Which pseudo file system acts as a interface to system and processes | /proc |
What is Systemd? | It is a binary subsystem for managing Linux startup and service control |