| command | description |
|---|---|
| . | current directory |
| .. | parent directory |
| cd | change to the home directory |
starts with the current directory (no need to specify directory in case of current directory)
find -name "*c*" -type d
| parameter | description |
|---|---|
| -name "c" | with name contains the letter c |
| -type d | which are a directory |
| -iname | like name but ignores case |
You can run the command on other directory (/full/path/to/dir) using:
find /full/path/to/dir -name "*c*" -type d
Find in folder projects all files, which name is README
find projects -name README
Find files, that are more than 13 < days old < 10
find . -mtime +10 -mtime -13
Find files, that are more than 13 < days old < 10 and use ls for the result
find . -mtime +10 -mtime -13 -ls
Find only files by name
find /path/to/search -name filename -type f
Find executable files
find /path/to/search -type f -executable
Counting how many things you find
find /path/to/search | wc -l
Find only directories with name AK without any files inside
find AK -maxdepth 1 -type d.
Find file in all machine
find / -name "filename"
| command | description |
|---|---|
| space | to go on the next page |
| g | go to the begining og man |
| G | go to the bottom of man |
if you don't know exactly command, which you're looking for
man -k <searchTeem>
| command | description |
|---|---|
| -a | show all folders, which begin with . (means the are hidden files) |
| -l | show long information about file |
| -F | show you type of file /=folder. @=link *=executable |
| -r | reverse the order |
| -t | sort by the time |
<folder> |
execute ls in folder |
command show you, where command is located
which cat
create directory with children, if need. for exmaple 1/2/3
mkdir -p
delete folder and all files in it
rm -rf <folder>
| parameter | description |
|---|---|
| -r | remove content |
| -f | without prompt for comfirmation |
Copy file1, file2, etc. to destination directory
cp src_file1 [src_fileN...] dest_dir
if folder not exists, create a folder (when copy folders)
cp -r
| command | description |
|---|---|
| mv dir firstdir | ename dir to firstdir |
| mv file1.text firstdir | remove file1.txtx in firstdir |
| mv file1 file2 | if file2 exists, it will overwrite file2 of the content of file1 |
| mv -i | it will ask, do you want to rename it or not |
show the tree of folders show the color of different types of files = folders, executable, etc.
tree -C
all users are allowed only to read file
chmod a=r
make special permissions by default for the folder and files in it
display the contents of file - convinient for short files
show file with numbers
cat -n <file>
browse through a text file - it works more quicker than less.
more features than more
output the begining (or top) portion of file
show 15 lines of file (by default it's 10 lines)
head -15 file.txt
output the ending (or bottom) portion of file
tail -15 file.txt
show 15 lines of file (by default it's 10 lines)
tail -f file
displays the data as it's being written to the file
| command | description |
|---|---|
sort <nameOfFile> |
sort text in alphabetical order |
sort -u <nameOfFile> |
sort text in alphabetical order and show only unique lines |
sort -r <nameOfFile> |
sort text in alphabetical order and reverse order |
| command | description |
|---|---|
| ctrl+X | exit from editor |
| ctrl+G | help of nano |
| parameter | description |
|---|---|
| -i | Perform a search,ignoring case |
| -c | Count the number of occurences in a file |
| -n | Precede output with line numbers |
| -v | Invert Match. Print lines that don't match |
Example
cat logs, where there is word "error"
cat Robustness.log | grep "error"
show the count of word error in file, ignore the case
grep -ci error setup.log
find word "we" and replace it to "akozyreva"
grep "we" -ir -H ./prodigy.txt
grep "we" -rl -H ./prodigy.txt | xargs sed -i "" 's/We/akozyreva/g'
how move the cursor in vim
^
k
<h l>
j
how move cursor in line
| parameter | description |
|---|---|
| ^ | move to the begining of line |
| $ | go to the end of line |
how move between words
| parameter | description |
|---|---|
| w | right one word |
| e | from left to right to the next word |
| 2w | right on the 2 words |
| b | left one word |
| parameter | description |
|---|---|
| x | remove the caracter under the cursor |
| dw | delete a word |
| d2w | delete 2 words |
| dd | delete a line |
| D | delete from the current position |
| I | insert in the beginning of line |
| parameter | description |
|---|---|
| a | Append text after the cursor [count] times. |
| A | Append text at the end of the line [count] times. |
| :x | same as wq |
| :n | position of the cursor on the line n |
| :$ | position of the cursor on the last line |
| :set nu | turn on numbering |
| :set nonu | turn off numbering |
| parameter | description |
|---|---|
r<charachter> |
replace the current character |
R<characnters> |
replace more than one character |
| cw | change the current word |
| cc | change the current line |
| c$ | change the text from the current position to the end of line! |
| C | same as c$ |
| ~ | reverse the case of character |
| parameter | description |
|---|---|
| yw | copy one word |
| yy | yank copy the current line |
y<position> |
copy the position |
| p | past the most recent deleted or yanked text |
| parameter | description |
|---|---|
| u | step previous |
| U | return all the line to it's original state |
| cltr+R | next step |
| parameter | description |
|---|---|
/<pattern> |
start a forward search |
?<pattern> |
start a reverse search |
| ctrl+O | go back to where you came from |
| % | find the ending of parentheses |
:s/<oldWord>/<newWord>/g |
change oldword to new in all line |
:s/<oldWord>/<newWord>/ |
change oldword to new in 1 occurence |
:%s/<oldWord>/<newWord>/g |
change every occurence in the whole file |
:%s/<oldWord>/<newWord>/gc |
change every occurence in the whole file with a prompt whether delete it or not |
| parameter | description |
|---|---|
| ctrl+G | show location in the file and the file status |
<numberOfLine>G |
go on the line |
| G | go to the bottom of file |
| gg | move to the start of the file |
this allow you to execute external commands
:!<name of command>
create a new file
:w <name_of_new_file>
v = visual mode
- Move the cursor to this line.
- Press v and move the cursor to the fifth item below. Notice that the text is highlighted.
- Press the : character. At the bottom of the screen :'<,'> will appear.
- Type w TEST , where TEST is a filename that does not exist yet. Verify that you see :'<,'>w TEST before you press .
- Vim will write the selected lines to the file TEST. Use :!dir or :!ls to see it. Do not remove it yet! We will use it in the next lesson.
| parameter | description |
|---|---|
r:<name of file> |
insert the text from old file to new file |
| r: !ls | reads the output of the ls command and puts it below the cursor |
vim but in only-read mode
| parameter | description |
|---|---|
| o | open up a line below the cursor and place you in Insert mode |
| O | open up a line above the cursor and place you in Insert mode |
tar
| parameter | description |
|---|---|
| c | create archive |
| x | extract files from the archive |
| t | display the table of contents (list) |
| v | be verbose (view files, which were extracted) |
| z | use compression |
| f file | use this file |
create archive
tar cf tars.tar Robustness.log
tar zcf tars.tgz Robustness.log
extract archive
tar xf tars.tar
show files in archive
tar tf tars.tar
create archive from folder
tar -zcvf archive-name.tar.gz directory-name
tar czf tars.tar ./.test
| command | description |
|---|---|
| gzip | compress files |
| gunzip | uncompress files |
| gzcat | concatenates compressed files |
| zcat | concatenates compressed files |
| command | description |
|---|---|
| du | Estimate file usage |
| du -k | Display sizes in Kilobytes |
| du -h | Display sizes in human readable format |
The “Home” button on a Macbook Pro keyboard: Fn + Left Arrow. The “End” button on a Macbook Pro keyboard: Fn + Right Arrow.
| parameter | description |
|---|---|
| * | matches zero or more characters |
| ? | matches exactly one character |
| ?? | matches 2 characters |
| / | escape character |
| *.txt | matches all files with txt extension |
| a?.txt | find a and one character.txt - for exmaple as.txt |
| mv *.txt notes | move all files with extension txt to folder notes |
| mv *.txt | delete all files with txt extension |
| parameter | description |
|---|---|
| > | redirect output to file |
| >> | redirect standard output to a file(appends to any existing contents) |
| < | redirect input from a file to a command |
| >/dev/null | redirect output to nowhere |
Examples
ls a*.txt > /dev/null
sort all output from fil aa.txt
sort < aa.txt
sort files from the files.txt and input the result in sorted_files.txt
sort < files.txt > sorted_files.txt
| command | description |
|---|---|
| diff file1 file2 | Compare two files |
| sdiff file1 file2 | Side-by-side comparison |
| vimdiff file1 file2 | Highlight differencies in vim |
Display the file type
file sales.data
Useful documentation
https://ss64.com/bash/cut.html
it only cut the output, not the file itself
show the first field of the line, separating by comma
cut -d':' -f1 /etc/passwd
https://www.thegeekstuff.com/2013/06/cut-command-examples
Command for creating shrotcut of command.
For example in order not to type ls-l all the time you can create alias of it and type only ll
command for delete aliases
see all env_variables in your system
Examples
printenv HOME
see the value of env_variable of HOME or
echo $HOME
for creating variable
export VAR="value"
but it should work only for terminal session
for deleting variable
to add constantly variable you need to add it in ~/.bash_profile
| command | description |
|---|---|
| ps | Display process status (without options - only processes in current session) |
| ps -e | everything, all processes |
| ps -eH | display all processes, full |
| ps -e --forest | display a processes tree |
| ps -f | full format listing |
| ps -u username | display usernames's processes |
| ps -p pid | display information for PID (process id, which can be found in ps command) |
| pstree | display processes in a tree format |
| top | interactive process viewer |
| htop | the same viewer but look cooler |
| command & | start command in background |
| Ctrl-c | kill the foreground process |
| Ctrl-z | suspend the foreground process |
| kill | kill a process by job number or PID |
cron runs sheduled jobs, for exmaple - run every Monday at 07:00
0 7 * * 1 /opt/weekly-report
| command | description |
|---|---|
| crontab file | install a new crontab from file |
| crontab -l | List your cron jobs |
| crontab -e | Edit your cron jobs |
| crontab -r | Remove all of your cron jobs |
su change user. by default it means superuser su - oracle change user on oracle
Allows you to execute command as another user, typically the superuser
run command as root
sudo command
Run as user1
sudo -u user1 command
return account name
whoami
yum allows to install packages from open Internet (firefox, for exmaple)
| command | description |
|---|---|
| yum search string | search for string |
| yum info [package] | display info |
| yum install -y package | install without saying yes |
| yum remove package | remove package |
rpm has the same functionality as yum but it installs packages, which are local stayed List all installed packages
rpm -qa
nohup uses for running processes in background - returns id of process
nohup ./start_test.sh &
Assuming the default tmux configuration is being used, novice tmux users please follow the instructions below to split the pane
To split the pane horizontally
- Press Ctrl+B
- Release pressed keys in Step 1
- Press " (on many keyboards, this is Shift+')
To split the pane vertically
- Press Ctrl+B
- Release pressed keys in Step 1
- Press % (on many keyboards, this is Shift+5)
To close a single pane in tmux, you need to either press Ctrl+d or type exit and press Return.
discard local changes in git
git clean -df
git checkout -- .
| command | description |
|---|---|
| lvmdiskscan | show all disks on computer |
| lsblk | show all disks but in tree structure |
| lsblk -p | show all disks with tree structure and full path |
| df -h | show all disks and their size |
| vgs | list all VLM groups |
| lvdisplay | list all lv_logical_layers |
| free -h | show memory (ozu/RAM) |
| command | description |
|---|---|
| docker image ls | look all images, which you have |
| docker ps -a | show all containers |
| docker info | info about docker |
| docker build -t dockerize-vuejs-app . | build container |
| docker rmi $(docker images -q). | delete all images |
| docker container ls |
for running docker container
docker run -p 80:80 akozyreva/docker-tutorial:part2
show ip address
ip a
on mac run the command
ifconfig
Explanation of output
| parameter | description |
|---|---|
| lo | show addres, which uses Linux by itslef for communication |
| eth0 | harware device |
echo public_key_string >> ~/.ssh/authorized_keys
cat id_rsa.pub >> ~/.ssh/authorized_keys
| command | description |
|---|---|
| ping HOST | send packages to the host in order to ckeck whether there is connection or not |
| ping -c COUNT HOST | send certain amount of packages |
| ping -c 3 google.com |
examine route (more detailed, than ping)
traceroute -n google.com
another command for checking network
tracepath -n google.com
look whether packets sends or not
| command | description |
|---|---|
| -n | Display numerical addresses and ports |
| -A | Display ASCII text output |
| -v | Verbose mode. Produce more output |
Can be used for checking network (in example bellow checks wheter connection is accepted to 80 port - http - or not)
telnet google.com 80