Options on the Ubuntu Main Interface

The options on the Ubuntu main interface are as follows: You can set environment variables. /Etc/profile: The first file used when the operating system customizes the user environment during logon. This file sets environment information for each user of the system. This file is executed when the user logs on for the first time. /Etc/environment: the second file used by the operating system during logon. Before the System reads your own profile, it sets the environment variable of the environment File. /Etc/bashrc: execute this file for every user running bash shell. When the bash shell is opened, the file is read .~ /. Profile: The third file used for logon is the. profile file. Each user can use this file to input shell information dedicated to their own use. When a user logs on, this file is only executed once! By default, it sets some environment variables to execute the user's. bashrc file. Use. profile to make the modification take effect. It is best to use source to execute. profile .~ /. Bashrc: The file contains bash information dedicated to a single user's bash shell. The file is read at login and each time a new shell is opened. Use source. bashrc to make the modification take effect. There are usually three ways to set environment variables: 1. Temporarily execute export PATH =/home/yan/share/usr/local/arm/3.4.1/bin: $ PATH 2. enable global settings for the current user ~ /. Bashrc, add row: export PATH =/home/yan/share/usr/local/arm/3.4.1/bin: $ PATH for effective: source. bashrc 3. Add the following global settings to $ vim/etc/profile: export PATH =/home/yan/share/usr/local/arm/3.4.1/bin: $ PATH to take effect source profile test: echo $ PATH =================================================== ========================================================== ======================================== in Ubuntu, if you have installed some software on your own, you will often find the appropriate shortcut options in the application on the system status bar, such as QQ. If not, manually add it. The method is: System-> preferences-> main menu. In this dialog box, you can add a new project in the editing process with the name and remarks. The most important thing is to browse the folder to the executable application software and click confirm. ========================================================== ========================================================== ================================ When you enter a shell command in the terminal, sometimes a command cannot be found, but sometimes it can be executed. Why? This is because of environment variable configuration. In the/etc/bash. bashrc file, the export PATH is placed for the last execution only once. It is best not to define multiple export paths. Configure the following environment variables: export JAVA_HOME =/opt/jdk1.6.0 _ 26 export ANDROID_JAVA_HOME = $ JAVA_HOMEPATH =/home/zhangcheng/workspace/complier/gcc/arm-2008q3/bin: $ JAVA_HOME/bin: $ PATHexport PATH if the content of the PATH is written separately and multiple exports are defined, the command not found prompt is displayed when the command is executed.