What does the star * has to do with the glob in python?

Question

I am new to python and I am using it for scripting.

I am trying to understand how glob works, also how is the star (*) related to glob and how does it work?

I have looked at many sources but i have been unable to find out what the star (*) means for glob

...anyhow -- for a question to be on-topic, it needs to be narrow and specific; thus, asking about not just a character, but a specific syntactical use. And almost certainly, there will already be Q&A entries in our database covering any specific usage you might want to ask about. — Charles Duffy, Jun 17 '19 at 14:59
Hey there! I would recommend doing some python research for [3.7.3](https://docs.python.org/3/library/glob.html) or for [2.7.16](https://docs.python.org/2/library/glob.html) — JROS, Jun 17 '19 at 14:59
To be fair, the Python documentation doesn't explain the glob patterns, only "according to the rules used by the Unix shell". — mkrieger1, Jun 17 '19 at 15:00
... which will lead to e.g. http://man7.org/linux/man-pages/man7/glob.7.html when searched for. — mkrieger1, Jun 17 '19 at 15:01
Sure; *if* that's what the OP wants to know, https://wiki.bash-hackers.org/syntax/pattern may be pertinent, with the understanding that no extensions are covered. However, the body of the question doesn't in any way back up that interpretation; it's only the title that mentions globs at all. — Charles Duffy, Jun 17 '19 at 15:01
Well, given "I am trying to understand how glob works" I think we can assume that the question is about glob patterns, not `*args`. — mkrieger1, Jun 17 '19 at 15:02
@JROS, that edit definitely brings the body in line with the title; I'd want to see the OP approve it as what they meant to ask before accepting an edit that speaks so loudly to a question's intent (and reopening the question, as the flagged duplicates would clearly no longer be suitable). — Charles Duffy, Jun 17 '19 at 15:41
@CharlesDuffy First, I think I made it very clear in the question that I am new to python, so apologies if my question caused so much inconvenience to you. However, thanks for your help! Second, when I was learning using the function '''glob''' in python, I tried to link it a little bit to the command '''find''' in Ubuntu such that it I can use '''find''' to look for files either with certain names or certain file extentions. Therefore, I just wanted to understand it further along with these symbols related to scripting. — BlockDiagram01, Jun 17 '19 at 16:09

brechmos · Accepted Answer · 2019-06-17T16:57:29.777

If we are talking about a '*' in the pattern, then, typically * just means "match any number of characters" or better "match 0 or more characters", so if we assume we have files in a directory: apple cherry custard green_apple then you can get lists of files for example:

import glob

print("glob.glob('a*') -> {}".format(glob.glob('a*'))) # match starting with 'a'

print("glob.glob('*a*') -> {}".format(glob.glob('*a*'))) # match anything that contains an 'a'

print("glob.glob('apple*') -> {}".format(glob.glob('apple*'))) # match if starts with 'apple'

print("glob.glob('*apple*') -> {}".format(glob.glob('*apple*'))) # match if 'apple' is in the filename

This would return

glob.glob('a*') -> ['apple']
glob.glob('*a*') -> ['apple', 'custard', 'green_apple']
glob.glob('apple*') -> ['apple']
glob.glob('*apple*') -> ['apple', 'green_apple']

This is a very simplistic view of what you can do with glob.glob.

What does the star * has to do with the glob in python?

1 Answers1