linux-commands

this file contain the linux commands i learned in work. with the day i learned it:

## usefull links:

### Linux tutorial:
https://linuxsurvival.com/linux-tutorial-introduction/

### print commands output to a file:
https://askubuntu.com/questions/420981/how-do-i-save-terminal-output-to-a-file
best option:    ** command |& tee output.txt **

Commands:


ls -list all the files in the directory
  ls -1: long list of files: with all information of the file
  
cd “XXX”: go to XXX directory (“/” super parent, “..” parent, “.” current )

cp -r “directory_to_copy” “to_directory” : copy the directory to the directory_to_copy to the directory to_copy   

pwd: print working directory

more “file”: show the file content

mv “file” “directory_to_move”: move the file to the directory or change its name

mkdir: make directory

cp “file” “directory_to_copy”:  copy the file to the directory 

rm “file”: remove the file
	rm -r “directory” : remove all the directory tree, with all its files.
	rm -rf "directory" : the -f force the remove

rmdir “directory”: remove the directory . only good for empty directory

chmod “u/g/o”  “+/-” “file”: change mode for the (user/group/other) to (+/-) of the rwx(read, write, execute) to the file.  

	chmod 777 <filenam>: each 7 stand for 1 (read) + 2 (write) + 4 (execute). use any combination you need : 3 = 1 (read) + 2 (write)

~ : shortcut for /home/user

Man “command” : open the manual for the command

Finger “name” : find the user name and directory of the name

Find “directory” “what to find (-name/)” “*file_name*” :find file_name by what to find from directory (if file name include wildcard need to worp the name with a quotes (“”))

cat “first_file” “second_file” … “N_file”  : concatenate (combine) the files and print them to the screen

cat “first_file” “second_file” > “new_file” : put the two files to a new file

cat “first_file” >> “secode_file” : append the first files to the second file

lpr “file” : print the file in the defult printer

lpr -P “some_printer” “file” : print the file in the some_printer printer

df :present the disc free space

ps aux : process status

cat “file1” “file1” | lpr -P “printer” : the pipe operator | send the output of one command to other command

grep “word_to_find” “file_to_search” : look for all patterns of word in a file

kill “pid” : kill the process with the ipd 
	kill -9 “pid” : kill immediately the ipd process

echo ‘string’ : output the string resived as an argument. Use as:
	echo ‘string’ > new file

touch “file.txt” : create a new file name file in txt format

curl ipv4.ident.me : print my public ip address


__open folder:__ nautilus "folder name" : open the folder with the file manager

__cutting, copy and pasting__ use: ctrl+shift+(x,c,v) (insted of just ctrl+(x,c,v)


# infinite loop that prints the command output to a file.
 
while true           // infinty loop
 
do
 
<commands....>       // the commands that the loop do every time
 
sleep 1              // wait between each iterate of the loop
 
done  >> log.txt     // redirect the output to a log file