Output number of lines in a text file to screen in Unix

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bash echo number of lines of file given in a bash variable

Was wondering how you output the number of lines in a text file to screen and then store it in a variable. I have a file called stats.txt and when I run wc -l stats.txt it outputs 8 stats.txt

I tried doing x = wc -l stats.txt thinking it would store the number only and the rest is just for visual but it does not work :(

Thanks for the help

A bash tutorial may help you: http://tldp.org/LDP/Bash-Beginners-Guide/html/ — glenn jackman, Oct 04 '12 at 18:05

score 18 · Answer 1 · answered Oct 04 '12 at 16:46

There are two POSIX standard syntax for doing this:

x=`cat stats.txt | wc -l`

or

x=$(cat stats.txt | wc -l)

They both run the program and replace the invocation in the script with the standard output of the command, in this case assigning it to the $x variable. However, be aware that both trim ending newlines (this is actually what you want here, but can be dangerous sometimes, when you expect a newline).

Also, the second case can be easily nested (example: $(cat $(ls | head -n 1) | wc -l)). You can also do it with the first case, but it is more complex:

`cat \`ls | head -n 1\` | wc -l`

There are also quotation issues. You can include these expressions inside double-quotes, but with the back-ticks, you must continue quoting inside the command, while using the parenthesis allows you to "start a new quoting" group:

"`echo \"My string\"`"
"$(echo "My string")"

Hope this helps =)

There's no need for 'cat' or any redirection/pipes - just do : x=$(wc -l /path/to/file.txt) — David Goodwin, Nov 05 '15 at 10:16

score 3 · Answer 2 · answered Oct 04 '12 at 16:39

3

you may try:

x=`cat stats.txt | wc -l`

or (from the another.anon.coward's comment):

x=`wc -l < stats.txt`

answered Oct 04 '12 at 16:39

none

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You can do it w/o `cat` & pipe as `x=$(wc -l – another.anon.coward Oct 04 '12 at 16:40
@gokcehan when I ran it ---- cat coursefile.txt | wc -l -----it worked. however when I tried to store it I got an error : -bash: x: command not found – Masterminder Oct 04 '12 at 16:43
don't forget the backticks (``) – none Oct 04 '12 at 16:44
@gokcehan I used the backquotes/backticks and it did not work, using bash shell if it helps – Masterminder Oct 04 '12 at 16:45
I can run it on my bash. what's the error you have? – none Oct 04 '12 at 16:46

Output number of lines in a text file to screen in Unix

2 Answers2