What does the ls ????? command do?

Question

I was trying to learn more about Linux and came across the command ls ????? and it displayed a few files in the directory but I am not really sure what it is specifically displaying. I tried to use the man to explain it further but I couldn't find anything. Could someone please explain?

Try man 7 glob. Also Is there a reason to use multiple question marks instead of an asterisk in filename expansion? — steeldriver, Jun 01 '20 at 17:32
@steeldriver I'm not sure, it was just a command I came across while trying to learn sys ad functions and it didn't make sense to me when I tried it. Edit: It looks like I specifically look for files/directories with 5 characters — rikito104, Jun 01 '20 at 17:39
@JeffSchaller, saying it's a dup of that other Q&A is a bit of a stretch. — Stéphane Chazelas, Jun 01 '20 at 19:22
@StéphaneChazelas I'd be happy to reopen it, but I understand this question as "I looked at man ls but don't understand what ls ????? is doing", and the other Q/A explains what the question-mark matches. I would love a better source-duplicate. — Jeff Schaller, Jun 01 '20 at 19:24
The ? character serves as a single-character "wild card" for filename expansion in globbing. It matches exactly one character. — David Kariuki, Jun 01 '20 at 23:10

Ralph_CCL · Answer 1 · 2020-06-01T17:53:53.020

-4

ls is a command on its own - try man ls for an explanation. ls ? may give a help summary in some Linux versions. ls with multiple ? is pointless as far as I know unless all the files listed have just five characters?.

edited Jun 01 '20 at 17:53

answered Jun 01 '20 at 17:47

Ralph_CCL

1

I found that the ls ????? will display files/directories with names of 5 characters. If I wanted to search for a file that I know started with R and was 5 characters but didn't remember the name I would us ls R???? and that would give me everything in that directory matching those requirements. – rikito104 Jun 01 '20 at 17:49
1

This question has very little to do with ls and much more to do with the question-marks... in fact, using a varying number of question marks demonstrates the point. – Jeff Schaller Jun 01 '20 at 17:50
It looks like it is matching for patterns, normally ls R* would give you any filenames of any length and R???? will do what you say. Perhaps look at man grep for more details on pattern matching. – Ralph_CCL Jun 01 '20 at 17:56
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ls /? would give a help summary... in DOS and Windows. (Except that the command there is called dir) I don't think I've ever seen /? or -? or such as giving a help text in any unix programs. ? by itself is a valid filename pattern (glob) for a one-letter filename, which you pretty much already know based on that last sentence. grep uses regular expressions, they're not the same as glob patterns. See here for the latter: https://mywiki.wooledge.org/BashGuide/Patterns – ilkkachu Jun 01 '20 at 18:08

What does the ls ????? command do?

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