Detect OS info

os_info.sh

#!/bin/bash
# Detects which OS and 
#  if it is Linux then it will detect which Linux Distribution,
#  if Mac(Darwin) will detect mac os x version, build number

OS=`uname -s`
REV=`uname -r`
MACH=`uname -m`

GetVersionFromFile()
{
  VERSION=`cat $1 | tr "\n" ' ' | sed s/.*VERSION.*=\ // `
}

if [ "${OS}" == "SunOS" ] ; then
  OS=Solaris
  ARCH=`uname -p`
  OSSTR="${OS} ${REV}(${ARCH} `uname -v`)"
elif [ "${OS}" == "AIX" ] ; then
  OSSTR="${OS} `oslevel` (`oslevel -r`)"
elif [ "${OS}" == "Linux" ] ; then
  KERNEL=`uname -r`
  if [ -f /etc/redhat-release ] ; then
    DIST='RedHat'
    PSUEDONAME=`cat /etc/redhat-release | sed s/.*\(// | sed s/\)//`
    REV=`cat /etc/redhat-release | sed s/.*release\ // | sed s/\ .*//`
  elif [ -f /etc/SUSE-release ] ; then
    DIST=`cat /etc/SUSE-release | tr "\n" ' '| sed s/VERSION.*//`
    REV=`cat /etc/SUSE-release | tr "\n" ' ' | sed s/.*=\ //`
  elif [ -f /etc/mandrake-release ] ; then
    DIST='Mandrake'
    PSUEDONAME=`cat /etc/mandrake-release | sed s/.*\(// | sed s/\)//`
    REV=`cat /etc/mandrake-release | sed s/.*release\ // | sed s/\ .*//`
  elif [ -f /etc/debian_version ] ; then
    DIST="Debian `cat /etc/debian_version`"
    REV=""
  fi
  if [ -f /etc/UnitedLinux-release ] ; then
    DIST="${DIST}[`cat /etc/UnitedLinux-release | tr "\n" ' ' | sed s/VERSION.*//`]"
  fi
  OSSTR="${OS} ${DIST} ${REV}(${PSUEDONAME} ${KERNEL} ${MACH})"
elif [ "${OS}" == "Darwin" ]; then
  type -p sw_vers &>/dev/null
  [ $? -eq 0 ] && {
    OS=`sw_vers | grep 'ProductName' | cut -f 2`
    VER=`sw_vers | grep 'ProductVersion' | cut -f 2`
    BUILD=`sw_vers | grep 'BuildVersion' | cut -f 2`
    OSSTR="Darwin ${OS} ${VER} ${BUILD}"
  } || {
    OSSTR="MacOSX"
  }
fi

echo ${OSSTR}