Linux - File Permissions

so till now we have seen how we can

create and manage your files and

directories now let us see how we can

see the permissions of files and

directories which we create into a Linux

operating system so into our LS - in

command we have seen we have list of

permissions which may define for files

and directories

now how you understand those particular

permissions and how we can change that

permissions that we are going to see

here so before we change first we should

understand how we can check for

deformations and what are the

permissions they are so basically if you

are talking about the file permissions

they are of two three types one is for

owner permission

so basically when a particular directory

or file is created that user is a owner

of the directory who has created the

file so we have to set the permission

for the owner basically the owner has

the full control information so that he

can create delete modify the existing

file or directory' the next one we have

that is called as a group formation now

if I am talking about the group

formation the owner decides which are

the users can be added in to its stroke

so he can add the users manually into

the group and then he can assign the

permission from the group of users

there is no limitation of the group of

users which and we can add into a users

group the next formation is for the

others so apart from the owner and the

group the public which are going to

access your file for them also we can

set the formation so there can be a full

control permission read-only what is a

permission you want you can give so

which are the kind of formations which

we can set for this particular trait

groups that is owner group and public

permission that is other permission that

we are going to see so as like your

Windows operating system and any other

particular permission which we define we

basically have read write and execute

permission even here so read permission

will provide a read access to us file or

a directory write formation will allow

you to create or modify or delete

that particular directory and its

content same way we have the execute so

execute formation provides you to access

the data or the particular list which we

have into the directory so basically we

have three type of formation if you

locate all this free diaper formation

that will be a full control or we can

also provide the permissions such as

read and execute or I just read write

and execute or just read permission so

the permissions can be modified or it

will be asked for you which permission

you want to provide on the owner group

and others now while we are defining the

permission as like we have seen we also

have the commands here to do everything

so here we are going to see how we can

check for deformation now if I want to

check for the permission generally your

Linux has Mbits assigned for deformation

like such way like here we can see the

file formation we generally have has

four different blocks where all these

blocks has a different permission sets

like here we can see it is just - means

nothing into it that means it is a file

formation one directory you can see it

is written as D that means it is a

directory and we are going to assign the

permission to a directory then the three

bit groups we have RW x that means read

write execute permission for this group

and the first group is your owner group

here we can define this is the fur which

has the owner permission as read write

and execute same way here read write and

execute for the directory same way this

block is for your groups so for user the

owner can add multiple users into the

group and the group will have this

formation which is called as a read and

execute we can find W is missing in

between that means it doesn't have great

information the next we have that is

read and execute formation again read

and execute is for public formation that

for others so this ten bits has one bit

over here which will be used for

identifying whether it is a directory or

offer the second three bits block will

be used for defining the form

for your owners again the next three big

blocks as we know this is blank but it's

still we have the - over here that means

it is black we do not have defined any

right formation but still the bits are

used so that three right is showing you

three bit blocks are used for the group

formation and the remaining three will

be for others same for your directories

as well so this trajectory and file

formation has the same kind of formation

same three groups we have that is owner

group and others only this will be

different that will be that file have

only - in first break while the

directory has D so if I want to change

or modify this formation or if I want to

assign a manual formation to a

particular directory and a file we have

a command called as chmod

so this chmod can be used for changing

the formation or creating or assigning

the permission for a specific directory

or a file but again this chmod can be

used in two different ways either you

can use the symbolic method like you can

add subtract the permissions by using

some of your symbols or you can use the

octal permission or of self permissions

that means you are going to use the

numbers for defining deformations so how

you are going to use this what type of

formations or both type of way how you

can create your permission or change

your permission for a directory and a

file that we are going to see into next

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