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How to fix Command Not Found error inLinux?

Command Not Found is a most common error in Linux, it means that your system has searched for

the command everywhere but couldn't find it. Well, its not really everywhere, there are some specific

places where the system searches for the command. This is all done using the PATH environment

variable. Commands are scripts and binary executables. PATH environment variable contains paths

of various directories, where your system looks for these executables.

In order to take a look at the $PATH variable in your system, run the following command in a

terminal.

[chia]$echo $PATH

/usr/sbin:/usr/bin:/usr/local/bin:/bin:/sbin:/home/chia/bin

A typical $PATH should look something like above. The value can vary from distro to distro but its

more or less similar. As you can see it contains the directories where one can commonly find various

binary executables of installed softwares - /bin, /usr/bin, /sbin etc. So, when you actually run a

command on your system, the command is looked upon in all the directories mentioned in PATH

until a match occurs.

Find the path of your command

To check the path of your command type

[chia]$which COMMAND_NAME

[chia]$which vim

/usr/bin/vim

[chia]$which ls

/bin/ls

Command not found even on su?

You might have faced a command not found error even when you su as root and you know you have

that command in your bin directories for root. There is a difference between su and su -. When you

login as root without the dash. Your login path remains

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This is not a supported way of doing things. Ubuntu does not have a root password by default.

If you need to accomplish something as root, enterCode:

sudo -i

in the terminal.

No worries, though. You can easily disable the root account again:

https://help.ubuntu.com/community/Ro...r root account

https://help.ubuntu.com/community/RootSudo#Re-disabling%20your%20root%20accounthttps://help.ubuntu.com/community/RootSudo#Re-disabling%20your%20root%20accounthttps://help.ubuntu.com/community/RootSudo#Re-disabling%20your%20root%20account