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Terminal - All commands - 11,491 results
for i in *.JPG; do convert -resize 1000x1000 -quality 85 $i `basename $i .png`-klein.png; done
sed -e 's/ .*//' -e 's/\.//' -e 's/^0*//' /proc/loadavg
2014-04-18 19:12:05
User: flatcap
Functions: sed
1

Show the current load of the CPU as a percentage.

Read the load from /proc/loadavg and convert it using sed:

Strip everything after the first whitespace:

sed -e 's/ .*//'

Delete the decimal point:

sed -e 's/\.//'

Remove leading zeroes:

sed -e 's/^0*//'
top -bn2|awk -F, '/Cpu/{if (NR>4){print 100-gensub(/.([^ ]+).*/,"\\1","g",$4)}}'
2014-04-18 17:48:05
User: ichbins
Functions: awk top
Tags: top cpu cpuinfo
0

This version is precise and requires one second to collect statistics. Check sample output for a more generic version and also a remote computer invocation variant. It doesn't work with the busybox version of the 'top' command but can be adjusted

tar -cf - file1 dir1/ dir2/ | md5sum
2014-04-17 14:33:44
User: snipertyler
Functions: tar
-1

Doesn't create a file

Make sure to list the files / directories in the same order every time.

cat dictionary.txt|while read a; do echo $a|cryptsetup luksOpen /dev/sda5 sda5 $a && echo KEY FOUND: $a; done
2014-04-16 18:49:53
User: rodolfoap
Functions: cat echo read
0

Lost your luks passphrase? You can always bruteforce from the command line. See the sample output, a simple command using a dictionary.

for a in {p,P}{a,A,4}{s,S,5}{s,S,5}; do echo $a|cryptsetup luksOpen /dev/sda5 $a && echo KEY FOUND: $a; done
2014-04-16 18:41:50
User: rodolfoap
Functions: echo
0

Lost your luks passphrase? You can always bruteforce from the command line. See the sample output, a simple command for the "pass" word, using combinations of upper/lowercase or number replacement. The generated combinations are:

for a in {p,P}{a,A,4}{s,S,5}{s,S,5}; do echo $a; done

pass

pasS

pas5

paSs

paSS

paS5

...

for id in `ls -1 ~/.ssh | grep -v "authorized\|known_hosts\|config\|\."` ; do echo -n "$id: " ; ssh-keygen -l -f .ssh/$id ; done
2014-04-16 14:12:20
User: drockney
Functions: echo grep id ssh-keygen
0

Find all private keys and dump their fingerprints.

cdn() { cd $(ls -1d */ | sed -n $@p); }
du -hsx * | sort -rh | head -10
(mountpoint -q "/media/mpdr1" && df /media/mpdr1/* > /dev/null 2>&1) || ((sudo umount "/media/mpdr1" > /dev/null 2>&1 || true) && (sudo mkdir "/media/mpdr1" > /dev/null 2>&1 || true) && sudo mount "/dev/sdd1" "/media/mpdr1")
2014-04-12 11:23:21
User: tweet78
Functions: df mkdir mount sudo umount
9

In my example, the mount point is /media/mpdr1 and the FS is /dev/sdd1

/mountpoint-path = /media/mpdr1

filesystem=/dev/sdd1

Why this command ?

Well, in fact, with some external devices I used to face some issues : during data transfer from the device to the internal drive, some errors occurred and the device was unmounted and remounted again in a different folder.

In such situations, the command mountpoint gave a positive result even if the FS wasn't properly mounted, that's why I added the df part.

And if the device is not properly mounted, the command tries to unmount, to create the folder (if it exists already it will also work) and finally mount the FS on the given mount point.

sudo tcpdump -i wlan0 -n ip | awk '{ print gensub(/(.*)\..*/,"\\1","g",$3), $4, gensub(/(.*)\..*/,"\\1","g",$5) }' | awk -F " > " '{print $1"\n"$2}'
gvfs-mount -e /path/to/mount
2014-04-11 14:58:42
User: flatcap
Tags: usb umount eject
-7

Unmount a USB device from the command line.

Use the GVFS (under Gnome) to unmount (and eject) the mounted USB device.

find . -name \*.svg -print0 | xargs -0 -n1 -P4 -I{} bash -c 'X={}; convert "$X" "${X%.svg}.png"'
2014-04-11 14:30:30
User: flatcap
Functions: bash find xargs
2

Convert some SVG files into PNG using ImageMagick's convert command.

Run the conversions in parallel to save time.

This is safer than robinro's forkbomb approach :-)

xargs runs four processes at a time -P4

echo thisIsATest | sed -r 's/([A-Z])/_\L\1/g'
2014-04-11 13:36:08
User: flatcap
Functions: echo sed
Tags: sed
1

Convert a camelCase string into snake_case.

To complement senorpedro's command.

jkhgkjh; until [[ $? -eq 0 ]]; do YOURCOMMAND; done
2014-04-11 08:19:15
User: moiefu
0

You want bash to keep running the command until it is successful (until the exit code is 0). Give a dummy command, which sets the exit code to 1 then keep running your command until it exits cleanly

< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c${1:-16};echo;
2014-04-07 10:07:22
User: opexxx
Functions: head tr
0

This snippet will produce an alpha-numeric 16 character password

find -type f -exec grep -q "regexp" {} \; -delete
2014-04-06 19:06:50
User: gumnos
Functions: find grep
Tags: find grep
1

Deletes files in the current directory or its subdirectories that match "regexp" but handle directories, newlines, spaces, and other funky characters better than the original #13315. Also uses grep's "-q" to be quiet and quit at the first match, making this much faster. No need for awk either.

grep -Rl "pattern" files_or_dir
2014-04-06 18:18:07
User: N1nsun
Functions: grep
Tags: awk find grep
0

Grep can search files and directories recursively. Using the -Z option and xargs -0 you can get all results on one line with escaped spaces, suitable for other commands like rm.

find . | xargs grep -l "FOOBAR" | awk '{print "rm -f "$1}' > doit.sh
2014-04-06 15:48:41
User: sergeylukin
Functions: awk find grep xargs
Tags: awk find grep
-1

After this command you can review doit.sh file before executing it.

If it looks good, execute: `. doit.sh`

<CTRL+Z>; fg
2014-04-06 14:21:08
User: kbrotheridge
-1

Saves opening another console terminal (eg. CTRL+ALT+F[n]) or opening another remote terminal.

Ctrl+Z pauses the current task and pushed it to the background, leaving you with a command prompt for those "Oh crap I forgot to change xyz before I ran that and it'll take forever if I Ctrl+C and start again..." situations. Typing 'fg' (shorthand for foreground, that's how I remember it) will resume the paused task.

echo $(sudo lshw -businfo | grep -B 1 -m 1 $(df "/path/to/file" | tail -1 | awk '{print $1}' | cut -c 6-8) | head -n 1 | awk '{print $1}' | cut -c 5- | tr ":" "-") | sudo tee /sys/bus/usb/drivers/usb/unbind
2014-04-06 12:06:29
User: tweet78
Functions: awk cut df echo grep head sudo tail tee tr
19

You have an external USB drive or key.

Apply this command (using the file path of anything on your device) and it will simulate the unplug of this device.

If you just want the port, just type :

echo $(sudo lshw -businfo | grep -B 1 -m 1 $(df "/path/to/file" | tail -1 | awk '{print $1}' | cut -c 6-8) | head -n 1 | awk '{print $1}' | cut -c 5- | tr ":" "-")

VAR=$(head -5)
2014-04-05 13:45:18
User: rodolfoap
Functions: head
Tags: read stdin head,
-2

Reads n lines from stdin and puts the contents in a variable. Yes, I know the read command and its options, but find this logical even for one line.

command_line 2>&1 | tee -a output_file
for i in {1..256};do p=" $i";echo -e "${p: -3} \\0$(($i/64*100+$i%64/8*10+$i%8))";done|cat -t|column -c120
2014-04-04 16:54:53
User: AskApache
Functions: cat column echo
5

Prints out an ascii chart using builtin bash! Then formats using cat -t and column.

The best part is:

echo -e "${p: -3} \\0$(( $i/64*100 + $i%64/8*10 + $i%8 ))";

From: http://www.askapache.com/linux/ascii-codes-and-reference.html

echo "this_is_a_test" | sed -r 's/_([a-z])/\U\1/g'