本文介绍了请问$ PWD总是等于$(真实路径。)的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

由于


  • 现代的Linux / UNIX / OSX(W / 的真实路径

  • 庆典(甚至在OSX)4+

  • A modern Linux/UNIX/OSX (w/ realpath)
  • bash 4+ (even on OSX)


"$PWD" == "$(realpath .)"

始终是真的吗?

推荐答案

它是pretty容易测试,这并非总是如此。

It's pretty easy to test that this is not always the case.

$ mkdir /tmp/realdir
$ cd /tmp/realdir
$ echo $PWD
/tmp/realdir
$ ln -s realdir /tmp/fakedir
$ cd /tmp/fakedir
$ echo $PWD
/tmp/fakedir
$ realpath .
/tmp/realdir

所以没有, $ PWD 并不总是相同的 $(真实路径。)

借助表明 PWD 变量是由内置的 CD 命令设置。默认的href=\"http://www.gnu.org/software/bash/manual/bashref.html#Bourne-Shell-Builtins\" rel=\"nofollow\">行为是:

The bash manual indicates that the PWD variable is set by the built-in cd command. the default behaviour of cd is:

符号链接后违约或带有-l选项

这意味着,如果CD插入符号链接的变量被相对于符号链接,而不是相对于物理路径解决。您可以通过使用 -P 选项更改此行为为 CD 命令。这将导致其报告中的 PWD 变量的物理目录:

This means that if you cd into a symlink the variable gets resolved relative to the symlink, not relative to the physical path. You can change this behavior for a cd command by using the -P option. This will cause it to report the physical directory in the PWD variable:

$ cd -P /tmp/fakedir
$ echo $PWD
/tmp/realdir

您可以使用 -P 选项来改变bash中的默认行为:

You can change the default behavior of bash using the -P option:

$ set -P
$ cd /tmp/fakedir
$ echo $PWD
/tmp/realdir
$ set +P
$ cd /tmp/fakedir
$ echo $PWD
/tmp/fakedir

这是当然的,尽管事实上,你可以执行后CD PWD 变量什么>它需要的值:

This is of course notwithstanding the fact that you can assign anything you want to the PWD variable after performing a cd and it takes that value:

$ cd /tmp/fakedir
$ PWD=/i/love/cake
$ echo $PWD
/i/love/cake

但是这不是真的你是问。

but that's not really what you were asking.

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