我认为以下几点应该有用。不过我对win32不太确定。

if [[ "$OSTYPE" == "linux-gnu"* ]]; then
        # ...
elif [[ "$OSTYPE" == "darwin"* ]]; then
        # Mac OSX
elif [[ "$OSTYPE" == "cygwin" ]]; then
        # POSIX compatibility layer and Linux environment emulation for Windows
elif [[ "$OSTYPE" == "msys" ]]; then
        # Lightweight shell and GNU utilities compiled for Windows (part of MinGW)
elif [[ "$OSTYPE" == "win32" ]]; then
        # I'm not sure this can happen.
elif [[ "$OSTYPE" == "freebsd"* ]]; then
        # ...
else
        # Unknown.
fi

在所有发行版上使用这应该是安全的。

$ cat /etc/*release

这就产生了这样的东西。

     DISTRIB_ID=LinuxMint
     DISTRIB_RELEASE=17
     DISTRIB_CODENAME=qiana
     DISTRIB_DESCRIPTION="Linux Mint 17 Qiana"
     NAME="Ubuntu"
     VERSION="14.04.1 LTS, Trusty Tahr"
     ID=ubuntu
     ID_LIKE=debian
     PRETTY_NAME="Ubuntu 14.04.1 LTS"
     VERSION_ID="14.04"
     HOME_URL="http://www.ubuntu.com/"
     SUPPORT_URL="http://help.ubuntu.com/"
     BUG_REPORT_URL="http://bugs.launchpad.net/ubuntu/"

根据需要提取/赋值给变量

注意:在一些设置。这也可能会给您一些可以忽略的错误。

     cat: /etc/upstream-release: Is a directory

对于我的.bashrc，我使用以下代码:

platform='unknown'
unamestr=$(uname)
if [[ "$unamestr" == 'Linux' ]]; then
   platform='linux'
elif [[ "$unamestr" == 'FreeBSD' ]]; then
   platform='freebsd'
fi

然后我会做如下的事情:

if [[ $platform == 'linux' ]]; then
   alias ls='ls --color=auto'
elif [[ $platform == 'freebsd' ]]; then
   alias ls='ls -G'
fi

虽然很丑，但很管用。如果你愿意，你可以用case代替if。

我在.bashrc中写了这些糖:

if_os () { [[ $OSTYPE == *$1* ]]; }
if_nix () { 
    case "$OSTYPE" in
        *linux*|*hurd*|*msys*|*cygwin*|*sua*|*interix*) sys="gnu";;
        *bsd*|*darwin*) sys="bsd";;
        *sunos*|*solaris*|*indiana*|*illumos*|*smartos*) sys="sun";;
    esac
    [[ "${sys}" == "$1" ]];
}

所以我可以这样做:

if_nix gnu && alias ls='ls --color=auto' && export LS_COLORS="..."
if_nix bsd && export CLICOLORS=on && export LSCOLORS="..."
if_os linux && alias psg="ps -FA | grep" #alternative to pgrep
if_nix bsd && alias psg="ps -alwx | grep -i" #alternative to pgrep
if_os darwin && alias finder="open -R"

下面是一种使用/etc/lsb-release和/etc/os-release(取决于您使用的Linux风格)检测基于Debian和RedHat的Linux操作系统的方法，并基于它采取简单的操作。

#!/bin/bash
set -e

YUM_PACKAGE_NAME="python python-devl python-pip openssl-devel"
DEB_PACKAGE_NAME="python2.7 python-dev python-pip libssl-dev"

 if cat /etc/*release | grep ^NAME | grep CentOS; then
    echo "==============================================="
    echo "Installing packages $YUM_PACKAGE_NAME on CentOS"
    echo "==============================================="
    yum install -y $YUM_PACKAGE_NAME
 elif cat /etc/*release | grep ^NAME | grep Red; then
    echo "==============================================="
    echo "Installing packages $YUM_PACKAGE_NAME on RedHat"
    echo "==============================================="
    yum install -y $YUM_PACKAGE_NAME
 elif cat /etc/*release | grep ^NAME | grep Fedora; then
    echo "================================================"
    echo "Installing packages $YUM_PACKAGE_NAME on Fedorea"
    echo "================================================"
    yum install -y $YUM_PACKAGE_NAME
 elif cat /etc/*release | grep ^NAME | grep Ubuntu; then
    echo "==============================================="
    echo "Installing packages $DEB_PACKAGE_NAME on Ubuntu"
    echo "==============================================="
    apt-get update
    apt-get install -y $DEB_PACKAGE_NAME
 elif cat /etc/*release | grep ^NAME | grep Debian ; then
    echo "==============================================="
    echo "Installing packages $DEB_PACKAGE_NAME on Debian"
    echo "==============================================="
    apt-get update
    apt-get install -y $DEB_PACKAGE_NAME
 elif cat /etc/*release | grep ^NAME | grep Mint ; then
    echo "============================================="
    echo "Installing packages $DEB_PACKAGE_NAME on Mint"
    echo "============================================="
    apt-get update
    apt-get install -y $DEB_PACKAGE_NAME
 elif cat /etc/*release | grep ^NAME | grep Knoppix ; then
    echo "================================================="
    echo "Installing packages $DEB_PACKAGE_NAME on Kanoppix"
    echo "================================================="
    apt-get update
    apt-get install -y $DEB_PACKAGE_NAME
 else
    echo "OS NOT DETECTED, couldn't install package $PACKAGE"
    exit 1;
 fi

exit 0

Ubuntu Linux的输出示例:

delivery@delivery-E5450$ sudo sh detect_os.sh
[sudo] password for delivery: 
NAME="Ubuntu"
===============================================
Installing packages python2.7 python-dev python-pip libssl-dev on Ubuntu
===============================================
Ign http://dl.google.com stable InRelease
Get:1 http://dl.google.com stable Release.gpg [916 B]                          
Get:2 http://dl.google.com stable Release [1.189 B] 
...            

bash manpage说变量OSTYPE存储了操作系统的名称:

OSTYPE自动设置为描述bash正在执行的操作系统的字符串。默认为system- 相关的。

它在这里被设置为linux-gnu。