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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Commands tagged wc from sorted by
Terminal - Commands tagged wc - 36 results
date +%A | cut -c $(( $(date +%A | wc -c) - 1 ))
2010-04-07 00:23:15
User: DaveQB
Functions: cut date wc
Tags: bash echo cut date wc

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.

find * \( -name "*.[hc]pp" -or -name "*.py" -or -name "*.i" \) -print0 | xargs -0 wc -l | tail -n 1
2010-03-25 18:58:29
User: neologism
Functions: find tail wc xargs
Tags: find xargs wc

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).

echo $(( `ulimit -u` - `find /proc -maxdepth 1 \( -user $USER -o -group $GROUPNAME \) -type d|wc -l` ))
2010-03-12 08:42:49
User: AskApache
Functions: echo wc

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.

OPTIMUM_P=$(( (`ulimit -u` - `find /proc -maxdepth 1 \( -user $USER -o -group $GROUPNAME \) -type d|wc -l`) / 2 ))

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.

find . -type f | xargs -P $OPTIMUM_P -iFNAME file FNAME | sed -n '/shell script text/p'

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:

cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}'

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.

cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}'

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.

alias busy='my_file=$(find /usr/include -type f | sort -R | head -n 1); my_len=$(wc -l $my_file | awk "{print $1}"); let "r = $RANDOM % $my_len" 2>/dev/null; vim +$r $my_file'
2010-03-09 21:48:41
User: busybee
Functions: alias awk find head sort vim wc

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. Drop this in your .bash_aliases and make sure that file is initialized in your .bashrc.

find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'
2009-09-08 08:25:45
User: karpoke
Functions: awk find tail wc xargs
Tags: awk find wc

This is really fast :)

time find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'


real 0m0.191s

user 0m0.068s

sys 0m0.116s

find . -type f -name '*.c' -exec wc -l {} \; | awk '{sum+=$1} END {print sum}'
2009-09-04 15:51:30
User: arcege
Functions: awk find wc
Tags: awk find wc

Have wc work on each file then add up the total with awk; get a 43% speed increase on RHEL over using "-exec cat|wc -l" and a 67% increase on my Ubuntu laptop (this is with 10MB of data in 767 files).

echo $((`eix --only-names -I | wc -l` * 100 / `eix --only-names | wc -l`))%
find . -maxdepth 1 -type f | wc -l
2009-07-31 14:53:29
User: guckes
Functions: find wc
Tags: wc

A simple "ls" lists files *and* directories. So we need to "find" the files (type 'f') only.

As "find" is recursive by default we must restrict it to the current directory by adding a maximum depth of "1".

If you should be using the "zsh" then you can use the dot (.) as a globbing qualifier to denote plain files:

zsh> ls *(.) | wc -l

for more info see the zsh's manual on expansion and substitution - "man zshexpn".

lsof -p <process_id> | wc -l
find . -name "*.sql" -print0 | wc -l --files0-from=-
2009-06-22 17:45:03
User: vincentp
Functions: find wc
Tags: find wc count line

This command gives you the number of lines of every file in the folder and its subfolders matching the search options specified in the find command. It also gives the total amount of lines of these files.

The combination of print0 and files0-from options makes the whole command simple and efficient.

dpkg -S /usr/bin/ls
2009-04-18 18:18:23
User: bwoodacre

'dpkg -S' just matches the string you supply it, so just using 'ls' as an argument matches any file from any package that has 'ls' anywhere in the filename. So usually it's a good idea to use an absolute path. You can see in the second example that 12 thousand files that are known to dpkg match the bare string 'ls'.