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Terminal - All commands - 12,071 results
watch -n 10 -d eval "sensors | grep RPM | sed -e 's/.*: *//;s/ RPM.*//'"
2015-04-07 14:28:32
User: omap7777
Functions: eval watch
1

Uses the lm-sensors package in Linux to display fan speed. Grep RPM is used to discover lines containing the text RPM, and sed is used to edit out everything but the RPM number. The watch utility is used to update the display every 10 seconds and -d highlights any changes from the previous value. The eval function of Bash is used to execute the command enclosed in the ".." string.

xset -display :0 q | grep ' Monitor is On' > /dev/null && xset -display :0 dpms force off || xset -display :0 dpms force on
2015-04-06 19:04:04
User: electrotux
Functions: grep
0

Queries whether the monitor is on according to DPMS. If true then turns the monitor off, if false turns it on. The -display option on xset means the command will work from sessions other than the console, such as ssh or a cron'd script. Command should display any errors if there are any problems (eg no X available), otherwise no output if successful.

mail [email protected]
2015-04-06 13:43:04
User: flatcap
Functions: mail
5

Welcome to Jon H. (@fart), the new maintainer of CommandLineFu.

.

In the absence of a forum, I encourage people welcome him, here, in the comments.

.

Also... What would you like to improve/change about the site?

pandoc --from=markdown --to=rst --output=README.rst README.md
curl -s http://host.net/url.html | grep magnet | sed -r 's/.*(magnet:[^"]*).*/\1/g'
function every() { sed -n -e "${2}q" -e "0~${1}p" ${3:-/dev/stdin}; }
2015-04-03 01:30:36
User: flatcap
Functions: sed
1

Thanks to knoppix5 for the idea :-)

Print selected lines from a file or the output of a command.

Usage:

every NTH MAX [FILE]

Print every NTH line (from the first MAX lines) of FILE.

If FILE is omitted, stdin is used.

The command simply passes the input to a sed script:

sed -n -e "${2}q" -e "0~${1}p" ${3:-/dev/stdin}

print no output

sed -n

quit after this many lines (controlled by the second parameter)

-e "${2}q"

print every NTH line (controlled by the first parameter)

-e "0~${1}p"

take input from $3 (if it exists) otherwise use /dev/stdin

{3:-/dev/stdin}
du -hsx * | sort -rh
cp -Rs dir1 dir2
2015-04-01 22:51:16
User: knoppix5
Functions: cp
2

dir1 and all its subdirs and subdirs of subdirs ... but *no files*

will be copied to dir2 (not even symbolic links of files will be made).

To preserve ownerships & permissions:

cp -Rps dir1 dir2

Yes, you can do it with

rsync -a --include '*/' --exclude '*' /path/to/source /path/to/dest

too, but I didn't test if this can handle attributes correctly

(experiment rsync command yourself with --dry-run switch to avoid

harming your file system)

You must be in the parent directory of dir1 while executing

this command (place dir2 where you will), else soft links of

files in dir2 will be made. I couldn't find how to avoid this

"limitation" (yet). Playing with recursive unlink command loop

maybe?

PS. Bash will complain, but the job will be done.

ssh user@server sudo date -s @`( date -u +"%s" )`
pdftk input.pdf output output.pdf user_pw YOURPASSWORD-HERE
ls | while read line; do ln -s "$(pwd)/$line" "/usr/bin/$line"; done
function every() { N=$1; S=1; [ "${N:0:1}" = '-' ] && N="${N:1}" || S=0; sed -n "$S~${N}p"; }
2015-03-21 23:44:59
User: flatcap
Functions: sed
1

Sometimes commands give you too much feedback.

Perhaps 1/100th might be enough. If so, every() is for you.

my_verbose_command | every 100

will print every 100th line of output.

Specifically, it will print lines 100, 200, 300, etc

If you use a negative argument it will print the *first* of a block,

my_verbose_command | every -100

It will print lines 1, 101, 201, 301, etc

The function wraps up this useful sed snippet:

... | sed -n '0~100p'

don't print anything by default

sed -n

starting at line 0, then every hundred lines ( ~100 ) print.

'0~100p'

There's also some bash magic to test if the number is negative:

we want character 0, length 1, of variable N.

${N:0:1}

If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

ps -ef | grep PROCESS | grep -v grep | awk '{system "kill -9" $2}
pgrep -lf processname | cut -d' ' -f1 | awk '{print "cat /proc/" $1 "/net/sockstat | head -n1"}' | sh | cut -d' ' -f3 | paste -sd+ | bc
nik=clf$RANDOM;sr=irc.efnet.org;expect -c "set timeout -1;spawn nc $sr 6666;set send_human {.1 .2 1 .2 1};expect AUTH*\n ;send -h \"user $nik * * :$nik commandlinefu\nnick $nik\n\"; interact -o -re (PING.:)(.*\$) {send \"PONG :\$interact_out(2,string)\"}"
2015-03-18 09:10:28
User: omap7777
7

Uses the extremely cool utilities netcat and expect.

"expect" logs in & monitors for server PING checks.

When a PING is received it sends the PONG needed to stay connected.

IRC commands to try: HELP, TIME, MOTD, JOIN and PRIVMSG

The "/" in front of IRC commands are not needed, e.g. type JOIN #mygroup

Learn about expect: http://tldp.org/LDP/LGNET/issue48/fisher.html

The sample output shows snippets from an actual IRC session.

Please click UP button if you like it!

sh <(curl hashbang.sh)
2015-03-15 21:02:01
User: lrvick
Functions: sh
5

Bash process substitution which curls the website 'hashbang.sh' and executes the shell script embedded in the page.

This is obviously not the most secure way to run something like this, and we will scold you if you try.

The smarter way would be:

Download locally over SSL

> curl https://hashbang.sh >> hashbang.sh

Verify integrty with GPG (If available)

> gpg --recv-keys 0xD2C4C74D8FAA96F5

> gpg --verify hashbang.sh

Inspect source code

> less hashbang.sh

Run

> chmod +x hashbang.sh

> ./hashbang.sh

sudo apt-get purge $(dpkg -l linux-{image,headers}-"[0-9]*" | awk '/ii/{print $2}' | grep -ve "$(uname -r | sed -r 's/-[a-z]+//')")
npm list -g --depth 0
syt() { pipe=`mktemp -u`; mkfifo -m 600 "$pipe" && for i in "$@"; do youtube-dl -qo "$pipe" "$i" & mplayer "$pipe" || break; done; rm -f "$pipe"; }
2015-03-14 01:48:20
User: snipertyler
Functions: mkfifo rm
2

Streams youtube-dl video to mplayer.

Usage:

syt 'youtube.com/link' 'anotherlinkto.video'

Uses mplayer controls

sudo sh -c 'echo 1 > /proc/sys/kernel/dmesg_restrict'
2015-03-13 20:54:45
User: Blacksimon
Functions: sh sudo
1

Linux offers an interesting option to restrict the use of dmesg. It is available via /proc/sys/kernel/dmesg_restrict.

You can check the status with:

cat /proc/sys/kernel/dmesg_restrict

Alternatively you can use sysctl:

sudo sysctl -w kernel.dmesg_restrict=1

To make your change persistent across reboot, edit a fille in /etc/sysctl.d/.

wmctrl -m | grep Name: | awk '{print $2}'
crontest () { date +'%M %k %d %m *' |awk 'BEGIN {ORS="\t"} {print $1+2,$2,$3,$4,$5,$6}'; echo $1;}
2015-03-12 19:56:56
User: CoolHand
Functions: awk date echo
0

usage = crontest "/path/to/bin"

This version of this function will echo back the entire command so it can be copied/pasted to crontab. Should be able to be automagically appended to crontab with a bit more work. Tested on bash and zsh on linux,freebsd,aix

crontab -l -u USER | grep -v 'YOUR JOB COMMAND or PATTERN' | crontab -u USER -
2015-03-11 13:10:47
User: Koobiac
Functions: crontab grep
1

The "-u USER" is optional if root user is used

sudo iptables -A INPUT -m limit --limit 2000/sec -j ACCEPT && sudo iptables -A INPUT -j DROP
2015-03-09 20:16:17
User: qdrizh
Functions: iptables sudo
Tags: iptables
1

VPS server hosts suspect DOS attack if PPS is too high. This limits packets at the interface level. Do "sudo apt-get install iptables-persistent" to make persistent, or, if you already have, reconfigure with "sudo dpkg-reconfigure iptables-persistent"

echo 'export PROMPT_COMMAND="history -a; history -c; history -r; $PROMPT_COMMAND"' >> .bashrc