CODEWITHSUNDEEP
pythonlinuxbashshellunix
pam
pam

Reputation: 1265

Shell: Prompt user to enter a directory path

I'm looking for a Bash equivalent of Python's os.path.join. I'm trying to prompt the user for a directory path, which then will be used (with the help of path join equivalent) to do other stuff.

Upvotes: 1

Views: 2633

Answers (2)

Phillip
Phillip

Reputation: 77

You might be looking for the readlink command. You can use readlink -m "some/path" to convert a path to the canonical path format. It's not quite path.join but it does provide similar functionality.

Edit: As someone pointed out to me readlink is actually more like os.path.realpath. It is also a GNU extension and not available on all *nix systems. I will leave my answer here in case it still helps in some way.

Upvotes: 1

abarnert
abarnert

Reputation: 365835

It's perfectly safe to use, e.g., "${dirpath}/${filename}" in a bash script.

bash only understands POSIX-style pathnames. Even if you build a MinGW/native bash on Windows. That means / is always the path separator. And it means that it never hurts to put two slashes in a row, so even if $dirpath happens to end in '/', everything is fine.

So, for example:

$ cat join.sh
#!/bin/bash
echo -n 'Path: '
read dirpath
echo -n 'Filename: '
read filename
ls -l "${dirpath}/${filename}"
$ ./join.sh
Path: /etc/
Filename: hosts
-rw-r--r--  1 root  wheel  236 Sep 15  2014 /etc/hosts

In Python, it's not safe to just use / this way. Python handles native-format pathnames on POSIX and POSIX-like systems, but also handles native-format pathnames on Windows.*, in which the path separator is \, two backslashes have a special meaning in certain places, you have drive letters to worry about, etc. So, you have to use os.path.join to be portable.

* It also has code for classic Mac (which uses colons), VMS (which uses a mix of different things that you don't want to know about), etc., if you're using an old enough Python.

Upvotes: 2

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