Basic
commands:
ls -ltr (list in directory date n time wise)
more filename.txt
(To open the file n linux)
info grep (information
about grep command)
cd
(change directory)
pwd
(to know the current directory)
Linux
Commands For Developers:
1] man
Using this command you can get the usage and
description of all Linux commands. For example, if you want to know
about “ls” command and its options, just execute “man ls” command in the
terminal to list its usage and description.
Syntax: man <command name>
man ls
2] touch, cat and less
Touch:
Touch command is used to create any
type of file in Linux systems with “0” size. When working with Linux
you might want to create files in the server. You can make use of touch command
to do that.
Syntax: touch <filename>
touch demo.txt
cat:
Cat command is used to view the
contents of a file. You cannot edit the contents of the file using
cat. It just gives a view of the file. cat doesn’t support scrolling using
keyboard.
Syntax: cat <filename>
cat demo.txt
Less:
Less command also gives the view of a file. less
is very fast and you can use the arrow keys to scroll up and down to know the
start and end of the file. There is also “more” command, which is used to view
the file but it allows only forward scrolling using “enter” key. It doesn’t
support backward scrolling.
Syntax: less <filename>
more
<filename>
3] Grep:
Grep command is used for searching
specific string patterns in a file.
Syntax: grep "<search
string>" <filename>
grep
"rahul" test.txt
grep --color -r "text" *
Note:
r means recursive. This will find for 'text' in all files
in that directory.
4] tar
tar command is used to create and extract
archive files. “-cf” and “-xf” flags are used for creating and
extracting archives.
Syntax: tar <options>
<archive-name> <file/folder name>
Let’s create a tar archive out of
test.txt file
tar -cf test.tar test.txt
Let’s extract the test.tar archive to
the destination folder “demo” using “-C” flag.
tar -xf test.tar -C /root/demo/
5] find
Find command is used for finding files. You can
find the files using its name with “-name” flag.
find -name test.txt
You can also find folder using its name by using”/ -name” flag.
find / -name passwd
6] diff
diff command is used to find the difference between
two files. Diff command analyses the files and prints the lines
which are different. Let’s say we have two files test and test1. you can find
the difference between the two files using the following command.
Syntax: diff <filename1> <filename2>
diff test.txt test1.txt
7] Uniq
uniq command is used for filtering out
the duplicate line in a file.
Syntax: uniq <filename>
uniq test.txt
8] Copy Files or Folders
8.1) Copy single file demo.txt to destination directory data:
$ cp demo.txt data
8.2) Copy 2 files demo.txt and demo.txt1 to destination absolute path directory /home/usr/rapid/ :
$ cp demo.txt demo.txt1 /home/usr/rapid/
8.3) Copy directory src to absolute path directory /home/usr/rapid/ :
$ cp src /home/usr/rapid/
9] Move/Rename
9.1) Move demo.txt demo.txt1 files to /home/usr/rapid/ directory:
$ mv demo.txt demo.txt1 /home/usr/rapid/
9.2) Rename file main.c to main.bak:
$ mv main.c main.bak
8] Copy Files or Folders
8.1) Copy single file demo.txt to destination directory data:
$ cp demo.txt data
8.2) Copy 2 files demo.txt and demo.txt1 to destination absolute path directory /home/usr/rapid/ :
$ cp demo.txt demo.txt1 /home/usr/rapid/
8.3) Copy directory src to absolute path directory /home/usr/rapid/ :
$ cp src /home/usr/rapid/
9] Move/Rename
9.1) Move demo.txt demo.txt1 files to /home/usr/rapid/ directory:
$ mv demo.txt demo.txt1 /home/usr/rapid/
9.2) Rename file main.c to main.bak:
$ mv main.c main.bak
