bash, csh, zsh 等 shell
    bourne Again SHell
    惯用的关机命令：Shutdown
    =============
    GNOME
    KDE
    cal 日历
    bc
    TAB 补全命令
    CTRl+D按键 输入结束 P121 EOF end of file 代替exit
    CTRl+C 中断当前程序
    ls -lht 列出文件大小时用K M，而不是字节数
    绝对路径：以斜杠开始的路径
    相对路径：不以斜杠开始的路径
    *ROOT用户对文件的操纵不受权属标志的限制
    ll
    ls -al
    chmod 777 test 改变文件属性
    chmod:改变文件的权限。
    chgrp:改变文件所属用户组。
    chown:改变文件所有者。
    http://www.cnblogs.com/avril/archive/2010/03/23/1692809.html LINUX 修改文件权限命令
    touch 创建新文件或者修改时间

    • head tail
    • grep 根据字符匹配来查看文件部分内容
    • wc
    • gzip、bzip2、tar
    • zip unzip
    • who
    • passwd
    • su
    • chown
    • chmod
    • ps 查看系统中的进程 ps aux
    • kill 、top
    • uname -a -r 显示系统信息
    • =================================================
    • 网络命令
    • ifconfig 管理网络设备
    • route
    • dhclient ftp wget（重要下载工具）
    • echo
    • 脚本的执行

    命令行的基本操作的快捷键

    1. 原来格式为表格（table），转换较复杂，未转换，需要手动复制一下
    2. {"cells":[{"verticalAlign":"middle","wrap":true,"value":"1\n2\n3\n4\n5\n6\n7\n8\n9\n10\n11\n12"},{"verticalAlign":"middle","wrap":true,"value":"# Ctrl + l - 清屏\n# Ctrl + A - 光标移到行首\n# Ctrl + E - 光标移到行尾\n# Ctrl + W - 清除光标之前一个单词\n# Ctrl + K - 清除光标到行尾的字符\n# Ctrl + T - 交换光标前两个字符\n# Ctrl + V - 输入控制字符 如Ctrl+v ,会输入^M\n# Ctrl + F - 光标后移一个字符\n# Ctrl + B - 光标前移一个字符\n# Ctrl + H - 删除光标前一个字符\n# N++F - 光标后移N个单词，N为1时可省略\n# N++B - 光标前移N个单词，N为1时可省略","inlineStyles":{"font-family":[{"from":0,"to":15,"value":"Courier New"},{"from":16,"to":35,"value":"Courier New"},{"from":36,"to":55,"value":"Courier New"},{"from":56,"to":79,"value":"Courier New"},{"from":80,"to":103,"value":"Courier New"},{"from":104,"to":126,"value":"Courier New"},{"from":127,"to":161,"value":"Courier New"},{"from":162,"to":183,"value":"Courier New"},{"from":184,"to":205,"value":"Courier New"},{"from":206,"to":228,"value":"Courier New"},{"from":229,"to":254,"value":"Courier New"},{"from":255,"to":280,"value":"Courier New"}],"color":[{"from":0,"to":15,"value":"#008200"},{"from":16,"to":29,"value":"#008200"},{"from":29,"to":35,"value":"#ff0000"},{"from":36,"to":48,"value":"#008200"},{"from":48,"to":55,"value":"#ff0000"},{"from":56,"to":79,"value":"#008200"},{"from":80,"to":103,"value":"#008200"},{"from":104,"to":126,"value":"#008200"},{"from":127,"to":161,"value":"#008200"},{"from":162,"to":183,"value":"#008200"},{"from":184,"to":205,"value":"#008200"},{"from":206,"to":228,"value":"#008200"},{"from":229,"to":254,"value":"#008200"},{"from":255,"to":280,"value":"#008200"}]}}],"widths":[70,774],"heights":[40]}

    X windows 与命令行模式的切换Ctrl+Alt+F1-F6
    Ctrl+Alt+F7
    exit 该用户退出linux
    ================================
    硬链接 文件—索引节点—索引号
    /符号链接