【开源 Mac 工具推荐之 5】tldr：简洁明了的命令行手册显示工具

简介

在大家日常在 macOS/Linux 上使用 Shell 的时候，常常会遇到一些不太熟悉的命令行指令，为此我们一般会查看一下该命令的使用手册（指南）。往往，大家都会使用 man <command> 这样一个非常传统的指令。但 man 也有一些缺点，比如显示的信息过于冗余等。

其实，GitHub 上有一个几乎完美的命令行手册显示工具，叫做 tldr。它能够提供比 man 简介明了多的说明。

tldr 项目地址：https://github.com/tldr-pages/tldr
（注：本文同时适用于 macOS 和 Linux）

想看看效果的话，可以看看这个例子。

举例

拿 unar 举个例子：

（顺便说一句，只能拿小的命令来举例，要不然 man 就会输出几千行几万行）

使用 man unar：

unar(1)                          User Commands                         unar(1)

NAME
       unar - extract archive file contents

SYNOPSIS
       unar [OPTION]... ARCHIVE [FILE]...

DESCRIPTION
       Extract FILEs or the contents of ARCHIVE.

OPTIONS
       -o, -output-directory DIRECTORY
              The directory to write the contents of the archive to.  Defaults
              to the current directory.

       -f, -force-overwrite
              Always overwrite files when a file to be unpacked already exists
              on disk.  By default, the program asks the user if possible,
              otherwise skips the file.

       -r, -force-rename
              Always rename files when a file to be unpacked already exists on
              disk.

       -s, -force-skip
              Always skip files when a file to be unpacked already exists on
              disk.

       -d, -force-directory
              Always create a containing directory for the contents of the
              unpacked archive.  By default, a directory is created if there
              is more than one top-level file or folder.

       -D, -no-directory
              Never create a containing directory for the contents of the
              unpacked archive.

       -p, -password PASSWORD
              The password to use for decrypting protected archives.

       -e, -encoding ENCODING
              The encoding to use for filenames in the archive, when it is not
              known.  If not specified, the program attempts to auto-detect
              the encoding used.  Use "help" or "list" as the argument to give
              a listing of all supported encodings.

       -E, -password-encoding ENCODING
              The encoding to use for the password for the archive, when it is
              not known.  If not specified, then either the encoding given by
              the -encoding option or the auto-detected encoding is used.

       -i, -indexes
              Instead of specifying the files to list as filenames or wildcard
              patterns, specify them as indexes, as output by lsar.

       -nr, -no-recursion
              Do not attempt to extract archives contained in other archives.
              For instance, when unpacking a .tar.gz file, only unpack the
              .tar file and not its contents.
unar(1)                          User Commands                         unar(1)

NAME
unar(1)                          User Commands                         unar(1)

NAME
       unar - extract archive file contents

SYNOPSIS
       unar [OPTION]... ARCHIVE [FILE]...

DESCRIPTION
       Extract FILEs or the contents of ARCHIVE.

OPTIONS
       -o, -output-directory DIRECTORY
              The directory to write the contents of the archive to.  Defaults
              to the current directory.

       -f, -force-overwrite
              Always overwrite files when a file to be unpacked already exists
              on disk.  By default, the program asks the user if possible,
              otherwise skips the file.

       -r, -force-rename
              Always rename files when a file to be unpacked already exists on
              disk.

       -s, -force-skip
              Always skip files when a file to be unpacked already exists on
              disk.

       -d, -force-directory
              Always create a containing directory for the contents of the
              unpacked archive.  By default, a directory is created if there
              is more than one top-level file or folder.

       -D, -no-directory
              Never create a containing directory for the contents of the
              unpacked archive.

       -p, -password PASSWORD
              The password to use for decrypting protected archives.

       -e, -encoding ENCODING
              The encoding to use for filenames in the archive, when it is not
              known.  If not specified, the program attempts to auto-detect
              the encoding used.  Use "help" or "list" as the argument to give
              a listing of all supported encodings.

       -E, -password-encoding ENCODING
              The encoding to use for the password for the archive, when it is
              not known.  If not specified, then either the encoding given by
              the -encoding option or the auto-detected encoding is used.

       -i, -indexes
              Instead of specifying the files to list as filenames or wildcard
              patterns, specify them as indexes, as output by lsar.

       -nr, -no-recursion
              Do not attempt to extract archives contained in other archives.
              For instance, when unpacking a .tar.gz file, only unpack the
              .tar file and not its contents.

       -t, -copy-time
              Copy the file modification time from the archive file to the
              containing directory, if one is created.

       -k, -forks visible|hidden|skip
              How to handle Mac OS resource forks.  visible creates
              AppleDouble files with the extension ".rsrc", hidden creates
              AppleDouble files with the prefix "._", and skip discards all
              resource forks.  Defaults to visible.

       -q, -quiet
              Run in quiet mode.

       -v, -version
              Print version and exit.

       -h, -help
              Display help information.

SEE ALSO
       lsar(1)

The Unarchiver                    2011-09-26                           unar(1)
(END)

可以看出，真的是——长长长长长长长……
而且，大部分命令其实我们都不怎么需要。

再看看 tldr unar：

  unar

  从归档文件中提取内容。
  更多信息：https://manned.org/unar.

  提取一个归档文件到当前目录：

    unar 归档文件

  提取一个归档文件到指定目录：

    unar -o 路径/到/目录 归档文件

  如果要提取的文件已经存在，则总是覆盖：

    unar -f 归档文件

  如果要提取的文件已经存在，则总是重命名：

    unar -r 归档文件

  如果要提取的文件已经存在，则总是跳过：

    unar -s 归档文件

还适配中文，并且信息非常简单集中，十分人性化。

了解差距了吧？

使用方法

tldr 有三种最常用的方法来安装：

1. npm 安装

npm install -g tldr

2. Python pip 安装

pip3 install tldr

3. Homebrew 安装

brew install tlrc

请大家注意，这些命令需要的环境可能没有预置在某些电脑上，这就需要你先去安装 Node.js、Python 3 或 Homebrew。本人有一些文章可供参考：

Node.js 的安装与使用（npm）
cnpm 的安装与使用
Python 更换 pip 源详细指南
Homebrew 安装与配置（macOS）
Homebrew安装与配置（Linux）

关于 Python 的安装，可以参考 Python 的官网（Python.org）。

其他更多操作，请参考项目地址上的说明。

本文完。

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