• 【Linux】head命令


    用途

    它是用来显示开头或结尾某个数量的文字区块


    全称

    head的全称即为head


    参数

    -q :隐藏文件名

    -v :显示文件名

    -c :<字节>显示字节数

    -n :<行数>显示的行数


    案例


    案例一:显示文件/etc/man_db.conf 的前5行

    [root@bigdata ~]# head -n 5 /etc/man_db.conf
    #
    #
    # This file is used by the man-db package to configure the man and cat paths.
    # It is also used to provide a manpath for those without one by examining
    # their PATH environment variable. For details see the manpath(5) man page.


    案例二:显示文件/etc/man_db.conf 除了最后5行所有的内容

    [root@bigdata ~]# head -n -5 /etc/man_db.conf
    #
    #
    # This file is used by the man-db package to configure the man and cat paths.
    # It is also used to provide a manpath for those without one by examining
    # their PATH environment variable. For details see the manpath(5) man page.
    #

    …..

    案例三:显示文件/etc/man_db.conf 前100个字节

    [root@bigdata ~]# head -c 100 /etc/man_db.conf
    #
    #
    # This file is used by the man-db package to configure the man and cat paths.


    案例二:显示文件/etc/man_db.conf 除了最后100个字节外所有的内容

    [root@bigdata ~]# head -c -100 /etc/man_db.conf
    #
    #
    # This file is used by the man-db package to configure the man and cat paths.
    # It is also used to provide a manpath for those without one by examining
    # their PATH environment variable. For details see the manpath(5) man page.
    #
    # Lines beginning with `#' are comments and are ignored. Any combination of
    # tabs or spaces may be used as `whitespace' separators.
    #
    # There are three mappings allowed in this file:

    ……

  • 相关阅读:
    git add 添加错文件 撤销
    工作流Activiti5.13学习笔记(一)
    instanceof, isinstance,isAssignableFrom的区别
    oracle表查询速度极慢的处理过程记录一下
    类里面的成员变量如果是public,为什么破坏封装
    IPv4 IPv6验证
    枚举使用
    XML之命名空间的作用(xmlns)
    XSD-JAVA
    jaxb
  • 原文地址:https://www.cnblogs.com/OliverQin/p/9474360.html
Copyright © 2020-2023  润新知