I am currently not on a Linux machine. Would the following command produce my wanted result?
ls | grep ".pdf" | wc
3 Answers
No, ".pdf" macthes way too much, e.g foo.pdfa and bpdf.
Furthermore, even if you don't have files wrongly matching, wc without options outputs the number of lines, words and bytes in the input, so you would get two numbers more than you're interested in. If you want grep in the mix, you could do ls | grep -E "\.pdf$" | wc -l, but unless you have a lot of pdf-files in that directory grep isn't needed, you can get by with ls *.pdf | wc -l.
Added later, when I got to think this through:
Also, grep can do the counting so if grep is in the mix, just add the -c option to grep instead of piping the output to wc -l, so ls | grep -cE "\.pdf$" or if you want to avoid counting directories named <something.pdf>: ls -l | grep -cE "^-.*\.pdf$".
answered May 21, 2016 at 13:27
Henrik supports the community
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this will also count folders matching the patternmagor– magor2016-05-21 14:42:54 +00:00Commented May 21, 2016 at 14:42
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I've added a solution to the answer that addresses that.Henrik supports the community– Henrik supports the community2016-05-21 17:12:44 +00:00Commented May 21, 2016 at 17:12
You should use
ls | grep ".pdf" | wc -l
The -l parameter will count only the number of resulted lines, while without the -l you would get other counts as well, like newline, word, and byte count. Note that this will count filenames (and folders as well) which contain the ".pdf" chain of characters.
To count only files ending with .pdf, you'd better use find :
find . -type f -name "*.pdf" | wc -l
Your shell should be able to do the filtering:
ls *.pdf | wc -l
or you have to make sure you match the end of filenames:
ls | grep "*\.pdf$" | wc -l
(notice the dollar sign).
Note: both of these will also match directories ending in ".pdf", if any.
Note 2: ls should behave as if you gave it option -1 as soon as you pipe its output. Otherwise, add this switch.
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add ls -1 or you will count lines but not filesMolbOrg– MolbOrg2016-05-21 13:32:43 +00:00Commented May 21, 2016 at 13:32
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@MolbOrg: see the 2nd note I've just added:
lsautomatically switches to "one-column mode" when you pipe its output.L. Levrel– L. Levrel2016-05-21 13:36:13 +00:00Commented May 21, 2016 at 13:36 -
Yes, true. didn't used that. nice to know now. tnx.MolbOrg– MolbOrg2016-05-21 15:10:37 +00:00Commented May 21, 2016 at 15:10
.pdf....this will count all files containing.pdf, like image.pdf0001.jpg....pdfcharacters, those will be counted too.