Unix cheat sheet

-
Inspite of years of working on Unix and Linux I still wasn't confident if I knew enough and hence read it in these holidays and I see that we can get our way through these amazing OS using the below commands:-

The OS uses the Filesystem to store data on the harddisk. They are different types of file storage, NTFS, FAT and etc. 

Commands to get your through!

pwd ==> Prints the working directory you are in. 


ls ==> just to list the files and directories, flags
  • -l  => output in list format
  • -a => show the hidden files
  • -h => output is more human, that is easier to understand 
cd ==> Change directory 

find location -type f -name filename   ==> to find the file that you have been looking for.

parted for partitioning ext4

mkfs ==> to create filesystems

echo $PATH  ==> print the path

env ==> to list the environment variables of 

ps -efl  ==> to print the details of the process that are running

ps $$ ==> to get PID of current shell

jobs ==> List background processes

!! ==> to run the last run command

history ==> very important to see what all commands have been run.

sleep 30 ==> to lock the terminal from taking any input for a certain amount of time.

whoami  ==> if you suffer from short term memory loss :) this helps you to know what is the log in you are using currently. 

nohup ==> prefixing it in front of a command makes the process to be immune to any futher signals until the completion of the task. 

& ==> appending this to a command runs it in the background.

fs <job_number> ==> brings the process to foreground.


Global profile (/etc/profile)
User profile (~/.bash_profile)



[million $ question is what is the difference between a job and a process? 
Jobs are one or more processes that are grouped together as a job, where job is a UNIX shell concept.]

Popular posts from this blog

Ansible - Error - stderr: E: There are problems and -y was used without --force-yes

-
Image
In case your tasks is to install some packages and it errors out as below - name: Install linux-headers apt: pkg={{item}} state=installed install_recommends=yes update_cache=yes with_items: - linux-headers-generic - dkms sudo: yes failed: [parallelsUbuntu] => (item=linux-headers-generic,dkms) => {"failed": true, "item": "linux-headers-generic,dkms"} stderr: E: There are problems and -y was used without --force-yes stdout: Reading package lists... Building dependency tree... Reading state information... The following extra packages will be installed:   cpp fakeroot gcc libfakeroot linux-headers-3.13.0-63   linux-headers-3.13.0-63-generic patch Suggested packages:   cpp-doc dpkg-dev debhelper gcc-multilib manpages-dev autoconf automake1.9   libtool flex bison gdb gcc-doc diffutils-doc The following NEW packages will be installed:   cpp dkms fakeroot gcc libfakeroot linux-headers-3
Read more

Error: SMTPIN_ADDED_BROKEN@mx.google.com

-
Some times we see the below in the email header information. SMTPIN_ADDED_BROKEN@mx.google.com The cause of the "...SMTPIN_ADDED_BROKEN@mx.google.com" is because of the 'https://' in the original Message-ID, which is not allowed. There could be some dodo systems which might be doing this and they would need to be tweaked to now allow message-id (see my earlier posts on what it means) and to have https!
Read more