There are several files you can set the environment variable in Ubuntu
/ Etc / profile: when you log in, the first file used by the operating system to customize the user environment settings file for each user environment information system, when a user first logs in, the file is executed.
/ Etc / environment: The second file operating system at login, the system before reading your own profile, set the environment variable environment file
~ / .Profile: used when logging in the third file is .profile files, each user can use the file input information specific to shell their own use, when a user logs in, the default file is performed only once! next, he set some environment variables, execute .bashrc file users.
/ Etc / bashrc: each user to perform a file operation when the bash shell bash shell is opened, the file is read.
~ / .Bashrc: This file contains dedicated to the bash shell bash your information, log on, and when every time you open a new shell when the the file is read.
There are generally three ways to set environment variables:
A temporary set
export PATH=/home/yan/share/usr/local/arm/3.4.1/bin:$PATH
Second, the current user's global settings
Open ~ / .bashrc, add the line:
export PATH=/home/yan/share/usr/local/arm/3.4.1/bin:$PATH
to validate
source .bashrc
Third, the global settings for all users
$ vim /etc/profile
Inside adding:
export PATH=/home/yan/share/usr/local/arm/3.4.1/bin:$PATH
to validate
source profile
Test echo $ PATH
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