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commandlinefu.com is the place to record those command-line gems that you return to again and again.

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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!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands tagged status from sorted by
Terminal - Commands tagged status - 11 results
$if [[ "$(sleep 1 | telnet -c <host> <port> 2>&1 | grep '^SSH')" == SSH* ]]; then <command when up>; else <command when down>; fi;
2016-02-02 13:06:51
User: paulera

This command telnet and and looks for a line starting with "SSH" - works for OpenSSH since the SSH banner is something like "SSH-2.0-OpenSSH_6.0p1 Debian-4+deb7u3". Then it triggers an action accordingly.

It can be packed as a script file to echo 0/1 indicating the SSH service availability:

if [[ "$(sleep 1 | telnet -c <host> <port> 2>&1 | grep '^SSH')" == SSH* ]]; then echo 1; else echo 0; fi;

Alternative uses:

Trigger an action when server is UP (using &&):

[[ "$(sleep 1 | telnet -c <host> <port> 2>&1 | grep '^SSH')" == SSH* ]] && <command when up>

Trigger an action when server is DOWN (using ||):

[[ "$(sleep 1 | telnet -c <host> <port> 2>&1 | grep '^SSH')" == SSH* ]] || <command when down>
stat /etc/my.cnf
watch -n 1 "awk 'NR==3 {print \"Signal strength = \" \$3 \"00 %\"}''' /proc/net/wireless"
watch -n 1 cat /proc/net/wireless
2012-06-07 10:38:21
User: cantormath
Functions: cat watch

Values will depend on the driver and the hardware specifics, so you need to refer to your driver documentation for proper interpretation of those values.

netstat -anpe
2011-12-06 18:27:09
User: anarcat
Functions: netstat

Lists all opened sockets (not only listeners), no DNS resolution (so it's fast), the process id and the user holding the socket.

Previous samples were limiting to TCP too, this also lists UDP listeners.

lxc-ls | sort -u | xargs -i sudo lxc-info -n {}
2011-10-28 11:10:02
User: Rhonda
Functions: sort sudo xargs
Tags: status lxc

This short snippet outputs the state of all containers available on your system. It is quite helpful to see which ones are running and which are stopped. Please notice that the "sort -u" is needed, otherwise running containers will be reported twice (see output of "lxc-ls" on its own for why)

apachectl fullstatus
for file in `cat urls.txt`; do echo -n "$file " >> log.txt; curl --head $file >> log.txt ; done
2010-10-19 02:54:13
User: Glutnix
Functions: echo file

urls.txt should have a fully qualified url on each line

prefix with

rm log.txt;

to clear the log

change curl command to

curl --head $file | head -1 >> log.txt

to just get the http status

git status | perl -F'\s' -nale 'BEGIN { $a = 0 }; $a = 1 if $_ =~ /changed but not updated/i; print $F[-1] if ( $a && -f $F[-1] )'
2010-10-15 07:58:14
Functions: perl
Tags: status git perl

Parse the output of git status.

Once the line '# Changed but not updated:' has passed print every last part of the line if it exists on disk.

curl -d api_key="$api_key" -d user_app_key="$user_app_key -d body="$body" -d post_method="default" http://api.ping.fm/v1/user.post
2009-09-04 23:20:33
User: matthewbauer

Updates your Ping.fm status and websites supported by ping.fm (like twitter, facebook, and google talk).

watch 'cat /proc/loadavg'
2009-09-03 20:10:46
User: 0disse0
Functions: watch
Tags: status watch

If you need to keep an eye on a command whose output is changing, use the watch command. For example, to keep an eye on your load average