Print certain system information。With no OPTION,same as -s。

    -a,--all     //print all information,in the following order.except omit -p and -i if unknows;

    -s,--kernel-name   //print the kernel name

    -n,--nodename  //print the network node hostname

    -r,--kernel-release    //print the kernel release

    -v,--kernel-version    //print the kernel version

    -m,--machine   //print the machine hardware name

    -p,--processor  //print the processor type or 'unknow'

    -i,--hardware-platform   //print the hardware platform or "unknow"

    -o,--operating-system    //print the operating system

       --help  //print the help and quit

       --version  //print the version info and quit