/bin/cat: Argument list too long

Question

I have 119766 files in a folder. They are CSV files. I want to find out total number of lines of all files.

I'm trying to run following command:

cat * |wc -l

But the following error occurrs:

-bash: /bin/cat: Argument list too long

How can I do that? Is there any way around this?

One thing I would like to add that total number of lines would be very large.

Answer 1

If you want a line-count for each individual file:

find . -type f -exec wc -l {} + | awk '! /^[ 0-9]+[[:space:]]+total$/'

I've excluded the total lines because there will be several of them with this many files being processed. The find ... -exec ... + will try to fit as many filenames onto a single command line as possible, but that will be a LOT less than 119766 files....probably only several thousand (at most) per invocation of wc, and each one will result in its own independent 'total' line.

If you want the total number of lines in all files combined, here's one way of doing it:

find . -type f -exec wc -l {} + | 
    awk '/^[ 0-9]+[[:space:]]+total$/ {print $1}' | 
    xargs | sed -e 's/ /+/g' | bc

This prints only the line counts on the total lines, pipes that into xargs to get the counts all on one line, then sed to transform the spaces into + signs, and then pipes the lot into bc to do the calculation.

Example output:

$ cd /usr/share/doc
$ find . -type f -exec wc -l {} + | 
    awk '/^[ 0-9]+[[:space:]]+total$/ {print $1}' | 
    xargs | sed -e 's/ /+/g' | bc 
53358931

Answer 2

Well, to give that cat from the question a new home, this should do:

find . -type f -exec cat {} + | wc -l

It executes a cat with the maximum acceptable number of filenames (+) again and again and pipes everything to wc. If you do not want to traverse subdirectories, a -maxdepth 1 has to be added to the find command, after the directory.

As an alternative, the --files0-from option to GNU wc could be used:

find . -type f -print0 | wc -l --files0-from=- | tail -1

This option makes wc read not the contents but the filenames from stdin, separated by null characters. With -print0, find will print those filenames null-byte separated. As wc will still print out line counts for every file, it is advisable to skip everything except the summary line at the end, hence the tail.

Both solutions have the advantage that they will work in any locale, whereas @cas' solutions have to be adapted ('total' is 'insgesamt' in German, e.g.).

Answer 3

If you have too many files, you probably don't want the information to go to stdout, so you can do something like this:

IFS="\n"; for file in find ./ -type f; do wc -l "$file" >> ~/linecount.txt; done