lInux 查看和添加环境变量

1. echo $PATH

xxx@xxx-VirtualBox:/home/openwrt_widora$ echo $PATH

/home/xxx/bin:

/home/cheng/.local/bin:

/usr/local/sbin:

/usr/local/bin:

/usr/sbin:

/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin

2. export

xxx@xxx-VirtualBox:/home/openwrt_widora$ export declare -x CLUTTER_IM_MODULE="xim" declare -x COMPIZ_CONFIG_PROFILE="ubuntu" declare -x DBUS_SESSION_BUS_ADDRESS="unix:abstract=/tmp/dbus-RvyK9kjBBX" declare -x DEFAULTS_PATH="/usr/share/gconf/ubuntu.default.path" declare -x DESKTOP_SESSION="ubuntu" declare -x DISPLAY=":0" declare -x GDMSESSION="ubuntu" declare -x GDM_LANG="en_US" declare -x GNOME_DESKTOP_SESSION_ID="this-is-deprecated" declare -x GNOME_KEYRING_CONTROL="" declare -x GNOME_KEYRING_PID="" declare -x GPG_AGENT_INFO="/home/cheng/.gnupg/S.gpg-agent:0:1" declare -x GTK2_MODULES="overlay-scrollbar" declare -x GTK_IM_MODULE="ibus" declare -x GTK_MODULES="gail:atk-bridge:unity-gtk-module" declare -x HOME="/home/cheng" declare -x IM_CONFIG_PHASE="1" declare -x INSTANCE="Unity" declare -x JOB="gnome-session" declare -x LANG="en_US.UTF-8" declare -x LANGUAGE="en_US" declare -x LC_ADDRESS="zh_CN.UTF-8" declare -x LC_IDENTIFICATION="zh_CN.UTF-8" declare -x LC_MEASUREMENT="zh_CN.UTF-8"

declare -x LC_MONETARY="zh_CN.UTF-8"

3. 临时添加环境变量 export /opt/buildroot-gcc463/usr/bin

xxx@xxx-VirtualBox:/$ export PATH=/opt/buildroot-gcc463/usr/bin

查看 echo $PATH

xxx@xxx-VirtualBox:/$ echo $PATH

/opt/buildroot-gcc463/usr/bin

4. 永久修改环境变量，影响当前用户