Not empty file, but "wc -l" outputs 0

Question

I have a non-empty file (even a big one, 400Ko), that I can read with less.

But if I try to output the number of lines with wc -l /path/to/file it outputs 0.

How can it be possible?

Answer 1

You can verify for yourself that the file contains no newline/linefeed (ASCII 10) characters, which would result in wc -l reporting 0 lines.

1. First, count the characters in your file:

   wc -c /path/to/file
   

   You should get a non-zero value.

2. Now, filter out everything that isn't a newline:

   tr -dc '\n' /path/to/file | wc -c
   

   You should get back 0.

3. Or, delete the newlines and count the result.

   tr -d '\n' | wc -c
   

   You should get back the same value as in step 1.

Answer 2

wc counts number of '\n' characters in the file. Could it be that your file does not contain one?

Here is the GNU source: https://www.gnu.org/software/cflow/manual/html_node/Source-of-wc-command.html

look for COUNT(c) macro.