Files & Permissions - Ch2

Question 1

FHS

Answer 1

File Hierarchy System ;

Specifies directory structure, type of info to store, & how shared

Question 2

Static directory

Answer 2

Holds static data & contains user and administrative commands, help files, library files, kernel and boot files;
/usr
/boot
/opt

Question 3

Dynamic directory

Answer 3

Holds variable data containing log and spool files, config files, temp files, personal user files
/var
/etc
/tmp
/home

Question 4

Static and shareable directories

Answer 4

/opt

/usr

Question 5

Static and unshareable

Answer 5

/boot

/etc

Question 6

Variable and shareable

Answer 6

/var/mail

/var/opt

Question 7

Variable and unshareable

Answer 7

/var/lock

/run

Question 8

/etc

Answer 8

holds sys config files

Question 9

/root

Answer 9

Default home dir of root user

Question 10

/media

Answer 10

To auto mount removable media

Question 11

/mnt

Answer 11

To temp mount a file system

Question 12

/bin and /usr/bin

Answer 12

To store admin commands

Question 13

/lib, /usr/lib, /lib64, /usr/lib64

Answer 13

To store 32 and 64 bit library routines needed by various commands and programs

Question 14

touch

Answer 14

Creates empty file and sets timestamp

Question 15

cat

Answer 15

Create short text file;
ex: cat > catfile1 then enter text;
Press Ctrl+d to save and return to shell prompt

Question 16

vi

Answer 16

Create and modify text files

Question 17

mkdir

Answer 17

Make directory

Question 18

ls

Answer 18

List directories

Question 19

ll

Answer 19

List details;

short for ls -l

Question 20

File / directory column information

Answer 20

Col 1: First char indicates file “-“ or dir “d”, remaining 9 char indicate permissions
Col 2: No of links
Col 3: Owner name
Col 4: Owning group
Col 5: Size in bytes (files) or blocks (dir)
Col 6,7,8: Mo, day and time of last modification
Col 9: Name of file or dir

Question 21

less

Answer 21

Text filter for viewing long text files, forward and backward, before entire file is loaded;

Question 22

more

Answer 22

Text filter for viewing long text files forward only

Question 23

cp

Answer 23

Copy files and directories

Question 24

mv

Answer 24

Move files and directories

Question 25

rm

Answer 25

Remove files and directories

Question 26

Regular files

Answer 26

May contain text or binary; | Files depicted by hyphen "-" when listed

Question 27

Directory files

Answer 27

Logical containers used to hold files and sub directories

Question 28

Executable files

Answer 28

Files that can be run; | Commands in binary format or shell scripts

Question 29

Symbolic link file

Answer 29

Shortcut to another file or directory

Question 30

Device file

Answer 30

File associated with system hardware used by kernel to communicate with hardware

Question 31

Permission classes

Answer 31

User Group Other (public)

Question 32

Permission types

Answer 32

r read w write x execute

Question 33

Permission modes

Answer 33

+ add - revoke = assign

Question 34

Octal permission notation

Answer 34

3 digit num sys (0-7) to express permissions for 3 user classes

Question 35

Octal permission weights

Answer 35

Weights assoc with each digit permission X X X | | | 4 2 1 ex. .. permission 2 would reference the middle digit ex. .. permission 6 would reference 2 most left digits

Question 36

chmod

Answer 36

Change permissions

Question 37

Symbolic permissions notation

Answer 37

x Execute r Read w Write ex... Add execute permiss bit for owner chmod u+x file1 -v ex... Add write permiss for group members and public chmod go+w file1 -v

Question 38

umask

Answer 38

User mask; | 3 digit octal value referencing r/w/e values for owner group and public

Question 39

Default permissions

Answer 39

Initial permissions (666) - umask

Question 40

chown

Answer 40

Change ownereship

Question 41

chgrp

Answer 41

Change group

Question 42

useradd

Answer 42

Create user account

Question 43

Metadata

Answer 43

Attributes associated with files... data about data

Question 44

inode

Answer 44

Index node; | storage space where metadata is stored

Question 45

Hard link

Answer 45

Mapping between one or more filenames and an inode

Question 46

ln

Answer 46

Command to create a hard link

Question 47

Soft link

Answer 47

Symbolic link which allows associations between files; Shortcut associations with files; Each softlink has a unique inode #

Question 48

ln -s

Answer 48

Command to create a soft link

Question 49

find

Answer 49

Searches for files that match specified criteria

Question 50

Period "."

Answer 50

Represents the current dir ex... find . -nam e newfile1 Search for file "find" in the current directory

Question 51

Tilda ~

Answer 51

Represents current user home dir

Question 52

locate

Answer 52

Discover all occurrences of specified string in file pathnames

Question 53

which

Answer 53

Prints path to command executed when run

Question 54

whereis

Answer 54

Prints path to command executed when run, including path to command's man pages

Question 55

type

Answer 55

Prints path to command executed when run

Question 56

setuid

Answer 56

Set user identifier; | provide non owners or groups ability to run executables with owner priveledges

Question 57

setgid

Answer 57

Set user identifier; provide non owners or groups ability to run executables with owner priveledges; Can be applied to shared dir also

Question 58

sticky bit

Answer 58

Applied to public directories for inhibiting file erasures by non-owners.