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I'm trying to list missing files in a sequence in the terminal. While many answers existed here, they are not generic enough that I managed to adapt it to my situation. So if you can make a generic enough answer that will work for more people, please do it.

I'm doing ls {369..422}.avi >/dev/null to list missing files but I can't use * to match anything that ends with .avi. How can I do this?

The numbers are not in the end of the file but in the middle. So I should need something like *numbers*.avi

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  • Do you want to match anything that ends in .avi, or anything that contains at least one number and ends in avi? Commented Sep 13, 2017 at 12:42
  • You probably would be better off using find with -regex Commented Sep 13, 2017 at 12:42
  • Anything that ends with ´.avi´ and has numbers in sequence on it Commented Sep 13, 2017 at 12:43
  • @RamanSailopal find will only find existing things. Freedo want's to check what's missing. Commented Sep 13, 2017 at 18:45

4 Answers 4

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ls *{369..422}*.avi >/dev/null

This will first generate patterns like

*369*.avi
*370*.avi
*371*.avi
*372*.avi
*373*.avi
*374*.avi

through the brace expansion, and then ls will be executed with these patterns, which will give you an error message for each pattern that can't be expanded to a name in the current directory.

Alternatively, if you have no files that contain * in their name:

for name in *{369..422}*.avi; do
    case "$name" in 
        '*'*) printf '"%s" not matched\n' "$name" ;;
    esac
done

This relies on the fact that the pattern remains unexpanded if it did not match a name in the current directory. This gives you a way of possibly doing something useful for the missing files, without resorting to parsing the error messages of ls.

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  • 1
    I think the final element is to redirect stdout, so that the missing files are reported to the terminal. Commented Sep 13, 2017 at 12:49
  • Thanks. This works! However I'm more confuse than before since seems no files are missing other than the expected ones! Well, thanks anyway! Commented Sep 13, 2017 at 13:03
  • 1
    @Freedo Well, it's better to not have files expected to be missing than to miss files expected to be existing... Commented Sep 13, 2017 at 13:13
  • Can't you just escape the * using a \ , this should prevent the problems with names containing it Commented Sep 13, 2017 at 19:55
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If you want *numbers*.avi, you can do:

ls *[0-9]*.avi

The [0-9] specifies a character class consisting of all characters between 0 and 9 in your locale. That should be all numbers. So you want to match 0 or more characters (*), then a number [0-9] and then 0 or more characters again (*).

If you need to have more than one number in sequence, use:

ls *[0-9][0-9]*.avi

Finally, if you have files in numerical order and just want to find the missing ones, you could also write a little loop:

for avi in {369..422}.avi; do [ -e "$avi" ] || echo "$avi missing"; done
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  • If I do your ls it will list all of files even after adding >/dev/null. Commented Sep 13, 2017 at 13:04
  • @Freedo yes, of course. You asked for *numbers*avi which will list everything. If you want to find only missing files, you need to give a better explanation in your question. You show file names that consist entirely of numbers ({369..422}.avi) but the say "The numbers are not in the end of the file but in the middle. So I should need something like *numbers.avi*" So I gave you what you asked for. Note that the loop in the end prints out the missing ones only. I find the loop more useful since you can trivially modify it to do something about each of the missing files. Commented Sep 13, 2017 at 13:41
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To list which of the *{369..422}*.avi patterns don't match any file, with zsh, you could do:

for p (\*{369..422}\*.avi) () {(($#)) || echo $p} $~p(N[1])

Or more verbosely:

for p (\*{369..422}\*.avi) () {
  if (($#)); then
    echo "$# file(s) matching $p"
  else
    echo >&2 No file matching $p
  fi
} $~p(N)

For files following a fixed pattern like: foo-123-bar.avi, you can also do:

expected=(foo-{369..422}-bar.avi)
actual=($^expected(N))
missing=(${expected:|actual})
print -l $missing

Some of the zsh-specific features in there:

  • x{1..20}y brace expansion expanding to x1y, x2y.... Copied by a few other shells since.
  • for var (values) cmd: short form of for loop
  • () compound-command args: anonymous function like in many other languages.
  • $~p: treat the content of $p as a glob (other shells do that by default, and even word splitting!)
  • (N[1]): glob qualifier for globs to expand to no argument when they don't match any file. [1] select the first matching file only as we only one to tell whether there has been any match.
  • $^array: brace-like expansion for the elements on an array
  • ${array1:|array2}: array subtraction
  • print -l: print in lines
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You can try with: ls *{369..422}*.avi

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  • I think the final element is to redirect stdout, so that the missing files are reported to the terminal. Commented Sep 13, 2017 at 12:55
  • a good catch with one minor update: we'd better redirect just the error messages to /dev/null rather than whole output ;). i.e. ls {369..422}.avi 2>/dev/null Commented Sep 13, 2017 at 14:41
  • my interpretation was that the OP wanted to find the missing files and wasn't interested in the matching files Commented Sep 13, 2017 at 14:59
  • Yeah this list all files and not the missing ones Commented Sep 23, 2017 at 9:24
  • You are absolutely right. I misread the author's question. Commented Sep 27, 2017 at 17:19

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