Commands tagged wc

calculate how many different lines between two files

Just want to post a Perl alternative.

Does not count hidden files ('.' ones).

change the time that you would like to have as print interval

and just use it to say whatever you want to

Count your source and header file's line numbers

For example for java change the command like this

find . -name '*.java' -exec cat {} \;|wc -l

Enhancement for the 'busy' command originally posted by busybee : less chars, no escape issue, and most important it exclude small files ( opening a 5 lines file isn't that persuasive I think ;) )

This makes an alias for a command named 'busy'. The 'busy' command opens a random file in /usr/include to a random line with vim.

It does not work without the verbose mode (-v is important)

There's nothing particularly novel about this combination of find, grep, and wc, I'm just putting it here in case I want it again.

Works similar to dpkg -S, but uses the locatedb and is thus inarguably a lot faster - if the locatedb is current.

Use bc for decimals...

Suppose you have 11 marbles, 4 of which are red, the rest being blue. The marbles are indistinguishable, apart from colour. How many different ways are there to arrange the marbles in a line? And how many ways are there to arrange them so that no two red marbles are adjacent?

There are simple mathematical solutions to these questions, but it's also possible to generate and count all possibilities directly on the command line, using little more than brace expansion, grep and wc!

The answer to the question posed above is that there are 330 ways of arranging the marbles in a line, 70 of which have no two red marbles adjacent. See the sample output.

To follow the call to marbles 11 4: after c=''; for i in $(seq $1); do c+='{b,r}'; done;, $c equals {b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}

After x=$(eval echo $c), and brace expansion, $x equals bbbbbbbbbbb bbbbbbbbbbr ... rrrrrrrrrrb rrrrrrrrrrr, which is all 2^11 = 2048 strings of 11 b's and r's.

After p=''; for i in $(seq $2); do p+='b*r'; done;, $p equals b*rb*rb*rb*r

Next, after y=$(grep -wo "${p}b*"

Finally, grep -vc 'rr'

Great idea camocrazed. Another twist would be to display a different man page based on the day of the year. The following will continuously cycle through all man pages:

Broaden your knowledge of the utilities available to you in no particular order whatsoever! Then use that knowledge to create more nifty one-liners that you can post here. =p

Takes a random number modulo the number of files in $dir, prints the filename corresponding to that number, and passes it as an argument to man.

There once was a day I needed this info.

Find the source file which contains most number of lines in your workspace

:)

The same as the other two alternatives, but now less forking! Instead of using '\;' to mark the end of an -exec command in GNU find, you can simply use '+' and it'll run the command only once with all the files as arguments.

This has two benefits over the xargs version: it's easier to read and spaces in the filesnames work automatically (no -print0). [Oh, and there's one less fork, if you care about such things. But, then again, one is equal to zero for sufficiently large values of zero.]

If you use HISTTIMEFORMAT environment e.g. timestamping typed commands, $(echo "1 2 $HISTTIMEFORMAT" | wc -w)

gives the number of columns that containing non-command parts per lines.

It should universify this command.

Another way of counting the line output of tail over 10s not requiring pv.

Cut to have the average per second rate :

tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log | cut -c-2

You can also enclose it in a loop and send stderr to /dev/null :

while true; do tail -n0 -f access.log>/tmp/tmp.log & sleep 2; kill $! ; wc -l /tmp/tmp.log | cut -c-2; done 2>/dev/null

A command to find out what the day ends in. Can be edited slightly to find out what "any" output ends in.

NB: I haven't tested with weird and wonderful output.

Finds all C++, Python, SWIG files in your present directory (uses "*" rather than "." to exclude invisibles) and counts how many lines are in them. Returns only the last line (the total).

There is a limit to how many processes you can run at the same time for each user, especially with web hosts. If the maximum # of processes for your user is 200, then the following sets OPTIMUM_P to 100.

This is very useful in scripts because this is such a fast low-resource-intensive (compared to ps, who, lsof, etc) way to determine how many processes are currently running for whichever user. The number of currently running processes is subtracted from the high limit setup for the account (see limits.conf, pam, initscript).

An easy to understand example- this searches the current directory for shell scripts, and runs up to 100 'file' commands at the same time, greatly speeding up the command.

I am using it in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html especially for the xargs command. Xargs has a -P option that lets you specify how many processes to run at the same time. For instance if you have 1000 urls in a text file and wanted to download all of them fast with curl, you could download 100 at a time (check ps output on a separate [pt]ty for proof) like this:

I like to do things as fast as possible on my servers. I have several types of servers and hosting environments, some with very restrictive jail shells with 20processes limit, some with 200, some with 8000, so for the jailed shells my xargs -P10 would kill my shell or dump core. Using the above I can set the -P value dynamically, so xargs always works, like this.

If you were building a process-killer (very common for cheap hosting) this would also be handy.

Note that if you are only allowed 20 or so processes, you should just use -P1 with xargs.