centos 之 設定環境變數,centos設定環境變數
方法一: 在/etc/profile檔案中添加變數【對所有使用者生效(永久的)】
用VI在檔案/etc/profile檔案中增加變數,該變數將會對Linux下所有使用者有效,並且是“永久的”。
[root@CentOS ~]# vi /etc/profile
在檔案末尾加上如下兩行代碼
PATH=/usr/local/webserver/php/bin:$PATH
export PATH
# /etc/profile
# System wide environment and startup programs, for login setup
# Functions and aliases go in /etc/bashrc
# It's NOT a good idea to change this file unless you know what you
# are doing. It's much better to create a custom.sh shell script in
# /etc/profile.d/ to make custom changes to your environment, as this
# will prevent the need for merging in future updates.
pathmunge () {
case ":${PATH}:" in
*:"$1":*)
;;
*)
if [ "$2" = "after" ] ; then
PATH=$PATH:$1
else
PATH=$1:$PATH
fi
esac
}
if [ -x /usr/bin/id ]; then
if [ -z "$EUID" ]; then
# ksh workaround
EUID=`id -u`
UID=`id -ru`
fi
USER="`id -un`"
LOGNAME=$USER
MAIL="/var/spool/mail/$USER"
fi
# Path manipulation
if [ "$EUID" = "0" ]; then
pathmunge /sbin
pathmunge /usr/sbin
pathmunge /usr/local/sbin
else
pathmunge /usr/local/sbin after
pathmunge /usr/sbin after
pathmunge /sbin after
fi
HOSTNAME=`/bin/hostname 2>/dev/null`
HISTSIZE=1000
if [ "$HISTCONTROL" = "ignorespace" ] ; then
export HISTCONTROL=ignoreboth
else
export HISTCONTROL=ignoredups
fi
export PATH USER LOGNAME MAIL HOSTNAME HISTSIZE HISTCONTROL
# By default, we want umask to get set. This sets it for login shell
# Current threshold for system reserved uid/gids is 200
# You could check uidgid reservation validity in
# /usr/share/doc/setup-*/uidgid file
if [ $UID -gt 199 ] && [ "`id -gn`" = "`id -un`" ]; then
umask 002
else
umask 022
fi
for i in /etc/profile.d/*.sh ; do
if [ -r "$i" ]; then
if [ "${-#*i}" != "$-" ]; then
. "$i"
else
. "$i" >/dev/null 2>&1
fi
fi
done
unset i
unset pathmunge
PATH=/usr/local/webserver/php/bin:$PATH
export PATH
要是剛才的修改馬上生效,需要執行以下代碼
[root@CentOS ~]# source /etc/profile
方法二:在使用者目錄下的.bash_profile檔案中增加變數【對單一使用者生效(永久的)】
用VI在使用者目錄下的.bash_profile檔案中增加變數,改變數僅會對目前使用者有效,並且是“永久的”。具體操作和方法1一樣,這裡就不在列舉代碼了。
方法三:直接運行export命令定義變數【只對當前shell(BASH)有效(臨時的)】
在shell的命令列下直接使用[export變數名=變數值]定義變數,該變數只在當前的shell(BASH)或其子shell(BASH)下是有效,shell關閉了,變數也就失效了,再開啟新shell時就沒有這個變數,需要使用的話還需要重新定義。例如
export PATH=/usr/local/webserver/php/bin:$PATH