shell技巧

#获取系统发行版名称
if grep -Eqi "CentOS" /etc/issue || grep -Eq "CentOS" /etc/*-release; then
    release='CentOS'
elif grep -Eqi "Debian" /etc/issue || grep -Eq "Debian" /etc/*-release; then
    release='Debian'
elif grep -Eqi "Ubuntu" /etc/issue || grep -Eq "Ubuntu" /etc/*-release; then
    release='Ubuntu'
else
    release='unknow'
fi

#获取系统版本号
if [[ -s /etc/redhat-release ]];then
    grep -oE  "[0-9.]+" /etc/redhat-release
else    
    grep -oE  "[0-9.]+" /etc/issue
fi
#获取系统位数
if [[ `getconf WORD_BIT` = '32' && `getconf LONG_BIT` = '64' ]] ; then
    bit='x64'
else
    bit='x32'
fi