Perform basic file management

Most of the files in the etc are owned by the root.

Relative path  : short path to the required/specified destination
Example : ls -al tmp

Absolute path  :  The full path for the required/specified destination
Example : ls -al /home/user/tmp

list only the directories,with out listing the files in it:   

[user@tcox1 ~]$ ls  -d tmp
tmp/

now,we will talk about the special directory called the reference directory.

[user@tcox1 ~]$ ls  -d 

.

.  is the reference for my current directory.

Direct to the home directory:

cd ~ this will take to my home directory

How can i get the environment variable?

[user@tcox1 etc]$ echo  $HOME

/home/user

for example:

[ec2-user@tcox1 etc]$ echo $HOME

/home/ec2-user

[user@tcox1 etc]$ echo "this is a test" > my text.txt
[user@tcox1 etc]$  file my text.txt
my text.txt:  ASCII text

it helps us to determine,what kind of files it was.(I mean it is a binary file or any other file type).

Globbing:

globbing means,it’s a wild card or a list of operator,that matches the one or more file.

Based on a defined or indicated path.

For example:

literally is a wild card,that matches anything in that directory.

But I can specify,what kind of file I want.

If I want to list the files in the /etc.

[user@tcox1 ~]$ ls -al /etc/c*

xxxxxxxxxxxxxxxxxxxxxxxx   2016  /etc/cetnos-release

xxxxxxxxxxxxxxxxxxxxxxxx    2016 /etc/cgconfig.conf

so,I can see globbing and more around and see things.

[user@tcox1 ~]$ ls -al  /usr/bin/*s????.?h

xxxxxxxxxxxxxxxxxxxxxx  2014  /usr/bin/lesspipe.sh

Any number of  characters before the letter s  -----> *
Give me a single character before the letter h ------> ?

how,you want,if you want to see the range of staff?

[user@tcox1 ~]$ ls -al  /usr/bin/[a-n]*.sh

xxxxxxxxxxxxxxxxxxxxxx  2014  /usr/bin/lesspipe.sh

Touch command importance:

If you did not create the file,the touch command will create the file for you.

If the file exists,it updates the time and date.

we can use globbing to touch multiple files.

speaking about the file properties:

it specify the file and file system stats.

stat -f test.txt

  File: "test.txt"

    ID: ca0100000000 Namelen: 255     Type: xfs

Block size: 4096       Fundamental block size: 4096

Blocks: Total: 2094336    Free: 906341     Available: 906341

Inodes: Total: 4193792    Free: 3950023

Note:

For copy command,it is always recommened to provide the absolute path.

Inorder to copy the directory,we have to use the –r,which means the recursive.

About redirecting directly to the home directory and its related sub-directory:

for example your in ec2-user and you want to home directory of the ec2-user:

[ec2-user@tcox1 ~]$ cd ~
/home/ec2-user

Example:

test:root~ # pwd

/root

test:root~ # cd ~kk

test:root/home/kk # pwd

/home/kk

Example for creating multiple directories at a time:

test:root~ # mkdir mkdir1/test1/test2/test3

mkdir: cannot create directory ‘mkdir1/test1/test2/test3’: No such file or directory

Ingeneral,the directory is created one at a time.

We can create multiple directories in following way:

test:root~ # mkdir -p mkdir1/test1/test2

test:root~ # pwd

/root

test:root~ # ls -la | grep mkdir1

drwxr-xr-x.  3 root root   19 Aug 17 15:38 mkdir1

test:root~/mkdir1/test1/test2 # pwd

/root/mkdir1/test1/test2