CentOS环境变量设置

[root@CentOS ~]# vi /etc/profile

在文件末尾加上如下两行代码PATH=/usr/local/webserver/php/bin:$PATHexport 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/$USER"fi# Path manipulationif [ "$EUID" = "0" ]; then    pathmunge /sbin    pathmunge /usr/sbin    pathmunge /usr/local/sbinelse    pathmunge /usr/local/sbin after    pathmunge /usr/sbin after    pathmunge /sbin afterfiHOSTNAME=`/bin/hostname 2>/dev/null`HISTSIZE=1000if [ "$HISTCONTROL" = "ignorespace" ] ; then    export HISTCONTROL=ignorebothelse    export HISTCONTROL=ignoredupsfiexport 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 fileif [ $UID -gt 199 ] && [ "`id -gn`" = "`id -un`" ]; then    umask 002else    umask 022fifor i in /etc/profile.d/*.sh ; do    if [ -r "$i" ]; then        if [ "${-#*i}" != "$-" ]; then            . "$i"        else            . "$i" >/dev/null 2>&1        fi    fidoneunset iunset pathmunge PATH=/usr/local/webserver/php/bin:$PATH 

export PATH 

要是刚才的修改马上生效，需要执行以下代码 

[root@CentOS ~]# source /etc/profile 

方法二：在用户目录下的.bash_profile文件中增加变量【对单一用户生效（永久的）】用VI在用户目录下的.bash_profile文件中增加变量，改变量仅会对当前用户有效，并且是"永久的"。具体操作和方法1一样，这里就不在列举代码了。方法三：直接运行export命令定义变量【只对当前shell（BASH）有效（临时的）】在shell的命令行下直接使用[export变量名=变量值]定义变量，该变量只在当前的shell（BASH）或其子shell（BASH）下是有效的，shell关闭了，变量也就失效了，再打开新shell时就没有这个变量，需要使用的话还需要重新定义。例如

export PATH=/usr/local/webserver/php/bin:$PATH