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I have a script that asks the user for the path to their desired directory

default_path =  '/path/to/desired/directory/'

user_path = raw_input("Enter new directory [{0}]: ".format(default_path)) or default_path

print user_path

The script has a "default" directory if no input is given. I want the script to "remember" the directory entered by the user. That is, the next time the script is run I want the default path to be the path input by the last user. Is this possible?

Maybe more generally, is there a good reference for writing command-line tools in python?

Brian Fitzpatrick
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    re: your general question. I wish there was. I like python as a language, but most CLI tools written in python are horrible. Most that I've used (including but not limited to the various openstack CLI tools like glance or nova-manage) have awful option processing and, worse, make no effort to produce output that can easily be re-used in other programs (like awk or sed) - it's like many/most python devs have no idea that unix tools are supposed to work WITH other tools and write them as if they're writing a windows CLI tool. This is not a problem with the language, it's a cultural problem. – cas May 11 '16 at 01:15
  • @cas, yes indeed. Would you know of a "shell-think by example for Python developers" ? – denis Jan 02 '17 at 12:12

3 Answers3

6

If you are maintaining the program, then make it store the history. In Python, use the readline library and make it store a history file.

If you don't want to modify the program, you can use a wrapper such as rlwrap.

rlwrap -H ~/.myprogram.history myprogram
Gilles 'SO- stop being evil'
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3

For this sort of thing, you want to use a configuration file of some sort. Usually a dotfile in the user's home directory will suffice for this sort of thing.

DopeGhoti
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3

You should store your information in a file, for which the location adheres to the XDG Base Directory Specification.

As your material is data and not config you should try if the environment variable XDG_DATA_HOME exists and create a file or a utility specific subdirectory under that, where you store the file. If that environment variable does not exists, default to ~/.local/share:

base_dir = os.environ.get('XDG_DATA_HOME', 
                  os.path.join(os.environ['HOME'], '.local', 'share'))
util_data_dir = os.path.join(base_dir, util_name)
Anthon
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