centos把php和mysql加入到环境变量_CentOS把php和mysql加入到环境变量

更新时间:2019-01-07    来源:linux    手机版     字体:

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环境变量


环境变量是和 Shell 紧密相关的,用户登录系统后就启动了一个 Shell 。对于 Linux 来说一般是 bash ,但也可以重新设定或切换到其它的 Shell 。根据发行版本的情况, bash 有两个基本的系统级配置文件: /etc/bashrc 和 /etc/profile 。这些配置文件包含两组不同的变量: shell 变量和环境变量。前者只是在特定的 shell 中固定(如 bash ),后者在不同 shell 中固定。很明显, shell 变量是局部的,而环境变量是全局的。环境变量是通过 Shell 命令来设置的,设置好的环境变量又可以被所有当前用户所运行的程序所使用。对于 bash 这个 Shell 程序来说,可以通过变量名来访问相应的环境变量,通过 export 来设置环境变量

方法一:直接运行命令

 代码如下 export PATH=$PATH:/usr/local/webserver/php/bin 和 export PATH=$PATH:/usr/local/webserver/mysql/bin

使用这种方法,只会对当前会话有效,也就是说每当登出或注销系统以后,PATH 设置就会失效,只是临时生效。


方法二:执行vi ~/.bash_profile修改文件中PATH一行,将/usr/local/webserver/php/bin 和 /usr/local/webserver/mysql/bin 加入到PATH=$PATH:$HOME/bin一行之后

这种方法只对当前登录用户生效


方法三:修改/etc/profile文件使其永久性生效,并对所有系统用户生效,在文件末尾加上如下两行代码

 代码如下

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

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

在文件末尾加上如下两行代码

 代码如下

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


要是刚才的修改马上生效,需要执行以下代码

 代码如下

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


这时再查看系统环境变量,就能看见刚才加的东西已经生效了

 代码如下

[root@CentOS ~]# echo $PATH
/usr/local/webserver/php/bin:/usr/lib/qt-3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

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