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Commands tagged Linux from sorted by
Terminal - Commands tagged Linux - 225 results
diff <(sort <(md5deep -b -r /directory/1/) ) <(sort <(md5deep -b -r /directory/2/)
2013-08-19 18:20:49
Functions: diff sort
Tags: bash Linux diff
0

Compares the md5 checksums of the contents of two directories, outputting the checksum and filename where any files differ. Shows only the file name, not the full path.

diff <(sort <(md5deep -r /directory/1/) |cut -f1 -d' ') <(sort <(md5deep -r /directory/2/) |cut -f1 -d' ')
2013-08-18 22:13:07
Functions: cut diff sort
Tags: bash Linux diff
1

Compute the md5 checksums for the contents of two mirrored directories, then sort and diff the results. If everything matches, nothing is returned. Otherwise, any checksums which do not match, or which exist in one tree but not the other, are returned. As you might imagine, the output is useful only if no errors are found, because only the checksums, not filenames, are returned. I hope to address this, or that someone else will!

wget -qO - http://www.asciiartfarts.com/random.cgi | sed -n '/<pre>/,/<\/pre>/p' | sed -n '/<table*/,/<\/table>/p' | sed '1d' | sed '$d' | recode html..ascii
for i in '/tmp/file 1.txt' '/tmp/file 2.jpg'; do ln -s "$i" "$i LINK"; done
2013-08-02 08:30:50
User: qwertyroot
Functions: ln
0

Replace

'/tmp/file 1.txt' '/tmp/file 2.jpg'

with

"$NAUTILUS_SCRIPT_SELECTED_FILE_PATHS"

for Nautilus script

Or with

%F

for Thunar action

If you linking the symlinks itself, but want to link to source files instead of symlinks, use

"`readlink -m "$i"`"

instead of

"$i"

like this:

for i in '/tmp/file 1.txt' '/tmp/file 2.jpg'; do ln -s "`readlink -m "$i"`" "$i LINK"; done

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

for i in {1..31}; do ls -1 *${YYYY}${MM}`printf "%02d" $i`* | wc -l; done
2013-07-26 07:08:04
User: Paulus
Functions: ls wc
Tags: bash Linux
0

RU: Найдет число файлов в папке по данной маске в цикле по дням месяца

du -m --max-depth=1 [DIR] | sort -nr
strace -ttvfo /tmp/logfile -s 1024 program
2013-07-06 08:19:29
User: ryanchapman
Functions: strace
Tags: Linux strace
0

How to figure out what a program is doing.

-tt detailed timestamps

-f also strace any child processes

-v be very verbose, even with common structures

-o write output to file

-s N capture up to N characters of strings, rather than abbreviating with ...

mogrify -resize SIZE_IN_PIXELS *.jpg
2013-07-05 14:14:04
User: o0110o
-1

Batch resize all images to a width of 'X' pixels while maintaing the aspect ratio.

This makes uses of ImageMagick to make life easier.

SSHPASS='your_password' sshpass -e ssh me@myhost.com
2013-06-03 12:26:40
User: djkadu
Functions: ssh
0

The above is OK if you not worried about security, as per sshpass man pages:

" The -p option should be considered the least secure of all of sshpass's options. All system users can see the password in the command line with a simple "ps" command."

So, instead what I do is use the -e option:

" -e The password is taken from the environment variable "SSHPASS"."

sshpass -p "YOUR_PASSWORD" ssh -o StrictHostKeyChecking=no YOUR_USERNAME@SOME_SITE.COM
2013-05-24 14:33:38
User: o0110o
Functions: ssh
3

You need to install "sshpass" for this to work.

apt-get install sshpass

du -mx [directory] | grep -P '^\d{4}' | sort -rn
2013-05-24 09:52:41
User: mc0e
Functions: du grep sort
Tags: bash Linux du
0

I don't like doing a massive sort on all the directory names just to get a small set of them. the above shows a sorted list of all directories over 1GB. use head as well if you want.

du's "-x" flag limits this to one file system. That's mostly useful when you run it on "/" but don't want "/proc" and "/dev" and so forth. Remember though that it will also exclude "/home" or "/var" if those are separate partitions.

the "-a" option is often useful too, for listing large files as well as large directories. Might be slower.

du -xB M --max-depth=2 /var | sort -rn | head -n 15
sudo apt-cache dumpavail | grep Package | cut -d ' ' -f 2 > available.packages
netstat -tuapen | grep LISTEN
fsarchvier probe simple
mencoder FILENAME.3gp -ovc lavc -lavcopts vcodec=msmpeg4v2 -oac mp3lame -lameopts vbr=3 -o FILENAME.avi
ssh user@remote "cat /remote/music/dir/*.mp3" | mpg123 -
2013-02-15 20:03:21
User: erix
Functions: mpg123 ssh
Tags: ssh Linux mpg123
-1

This is just a quick and dirty way to play remote audio files *locally* in your PC.

The best way is to mount the remote Music directory into the local FS, say by using sshfs:

sshfs user@remote:/remote/music/dir/ /mnt/other_pc/

/sbin/ifenslave -c bond0 eth1
2013-02-06 16:04:35
User: tduvally
1

This forces a bonded interface to switch to another slave in the bond as its active slave.

while true; do date; ps auxf | awk '{if($8=="D") print $0;}'; sleep 1; done
ifconfig | grep inet
2012-12-05 20:54:07
User: Karunamon
Functions: grep ifconfig
Tags: Linux ifconfig
0

Returns the IP, broadcast, and subnet mask of your interfaces absent any other extraneous info.

I know it's a bit lame, but I've created an alias for this when I *quickly* want to know what a system's IP is. Small amounts of time add up :)

for host in $HOSTNAMES; do ping -q -c3 $host && ssh $host 'command' & for count in {1..15}; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done &>/dev/null
for host in $MYHOSTS; do ping -q -c3 $H 2>&1 1>/dev/null && ssh -o 'AllowedAuthe ntications publickey' $host 'command1; command2' & for count in 1 2 3 4 5; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done
2012-11-13 23:12:27
User: a8ksh4
Functions: grep host jobs kill ping sleep ssh wc
0

Execute commands serially on a list of hosts. Each ssh connection is made in the background so that if, after five seconds, it hasn't closed, it will be killed and the script will go on to the next system.

Maybe there's an easier way to set a timeout in the ssh options...

for P in $(mount | awk '/type nfs / {print $3;}'); do echo $P; sudo umount $P && sudo mount $P && echo "ok :)"; done
2012-10-14 22:39:58
User: amatix
Functions: awk echo mount sudo umount
Tags: Linux mount nfs
0

`mount -o remount` doesn't pick up new NFS options (eg. timeo, soft, retrans, etc) so you need to do a full mount/remount cycle. This one-liner makes it quick and easy :) Update your fstab with the new options, then run it.

sudo lastb | awk '{if ($3 ~ /([[:digit:]]{1,3}\.){3}[[:digit:]]{1,3}/)a[$3] = a[$3]+1} END {for (i in a){print i " : " a[i]}}' | sort -nk 3
2012-09-11 14:51:10
User: sgowie
Functions: awk lastb sort sudo
0

The lastb command presents you with the history of failed login attempts (stored in /var/log/btmp). The reference file is read/write by root only by default. This can be quite an exhaustive list with lots of bots hammering away at your machine. Sometimes it is more important to see the scale of things, or in this case the volume of failed logins tied to each source IP.

The awk statement determines if the 3rd element is an IP address, and if so increments the running count of failed login attempts associated with it. When done it prints the IP and count.

The sort statement sorts numerically (-n) by column 3 (-k 3), so you can see the most aggressive sources of login attempts. Note that the ':' character is the 2nd column, and that the -n and -k can be combined to -nk.

Please be aware that the btmp file will contain every instance of a failed login unless explicitly rolled over. It should be safe to delete/archive this file after you've processed it.

s() { screen -d -RR -m -S "$1" -t "$USER"@"$1" ssh "$1"; }
2012-09-07 23:02:52
User: salamando
Functions: screen ssh
Tags: ssh screen Linux
5

Use as: $ s host1

Will ssh to remote host upon first invocation. Then use C-a d to detatch. Running "s host1" again will resume the shell session on the remote host. Only useful in LAN environment. You'd want to start the screen on the remote host over a WAN.

Adapted from Hack 34 in Linux Server Hacks 2nd Addition.