All commands (14,187)

  • If you're going to use od, here's how to suppress the labels at the beginning. Also, it doesn't output the \x, hence the sed command at the end. Remove it for space separated hex values instead Show Sample Output


    5
    echo -n "text" | od -A n -t x1 |sed 's/ /\\x/g'
    camocrazed · 2010-07-14 15:31:36 8

  • 1
    find . -name '*.?pp' -exec grep -H "string" {} \;
    rthemocap · 2010-07-14 15:10:23 5
  • Ssh to host1, host2, and host3, executing on each host and saving the output in {host}.log. I don't have the 'parallel' command installed, otherwise it sounds interesting and less cryptic.


    1
    for host in host1 host2 host3; do ssh -n user@$host <command> > $host.log & done; wait
    cout · 2010-07-14 14:55:31 3
  • Just use "od" and it can also dump in decimal or octal. (use -t x1 and not just -x or it confuses the byte order) There is a load of other formatting options, I'm not sure if you can turn off the address at the start of the line. Show Sample Output


    0
    echo "text" | od -t x1
    max_allan · 2010-07-14 14:53:25 3
  • I like this better than some of the alternatives using -exec, because if I want to change the string, it's right there at the end of the command line. That means less editing effort and more time to drink coffee. Show Sample Output


    2
    find . -name '*.?pp' | xargs grep -H "string"
    cout · 2010-07-14 14:41:07 5
  • first off, if you just want a random UUID, here's the actual command to use: uuidgen Your chances of finding a duplicate after running this nonstop for a year are about the same as being hit by a meteorite before finishing this sentence The reason for the command I have is that it's more provably unique than the one that uuidgen creates. uuidgen creates a random one by default, or an unencrypted one based on time and network address if you give it the -t option. Mine uses the mac address of the ethernet interface, the process id of the caller, and the system time down to nanosecond resolution, which is provably unique over all computers past, present, and future, subject to collisions in the cryptographic hash used, and the uniqueness of your mac address. Warning: feel free to experiment, but be warned that the stdin of the hash is binary data at that point, which may mess up your terminal if you don't pipe it into something. If it does mess up though, just type reset Show Sample Output


    0
    printf $(( echo "obase=16;$(echo $$$(date +%s%N))"|bc; ip link show|sed -n '/eth/ {N; p}'|grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'|head -c 17 )|tr -d [:space:][:punct:] |sed 's/[[:xdigit:]]\{2\}/\\x&/g')|sha1sum|head -c 32; echo
    camocrazed · 2010-07-14 14:04:53 10

  • -1
    grep -i '^DocumentRoot' /etc/httpd/conf/httpd.conf | cut -f2 -d'"'
    hm2k · 2010-07-14 13:30:36 3
  • Here's a version that uses perl. If you'd like a trailing newline: perl -pe 's/(.)/sprintf("\\x%x", ord($1))/eg; END {print "\n"}'


    1
    echo -n 'text' | perl -pe 's/(.)/sprintf("\\x%x", ord($1))/eg'
    putnamhill · 2010-07-14 12:20:42 3

  • 9
    indent -kr hello.c
    cp · 2010-07-14 07:16:15 4

  • 1
    tcpdump -i eth0 port 80 -w -
    freestyler · 2010-07-14 04:17:18 7
  • If shell escaping of the command is problematic, you can write the command to a file first: batch <somefile Or read it: read -re && echo "$REPLY" | batch Or, if your shell supports it, you can eliminate echo: read -re && batch <<<$REPLY ("man batch" lists 1.5 for me, but I don't know how widely it differs.)


    9
    echo 'some command' | batch
    kniht · 2010-07-14 03:08:31 3
  • As a user, deletes all your posts from a MyBB board (provided you have the search page listings of all your posts saved into the same directory this command is run from). Full command: for i in *; do cat $i | grep pid | sed -e 's/;/\ /g' -e 's/#/\ /g' -e 's/pid=/\ /g' | awk -F ' ' '{print $2}' >> posts.txt; done; for c in `cat posts.txt`; do curl --cookie name= --data-urlencode name=my_post_key=\&delete=1\&submit=Delete+Now\&action=deletepost\&pid=$c --user-agent Firefox\ 3.5 --url http://url/editpost.php?my_post_key=\&delete=1\&submit=Delete+Now\&action=deletepost\&pid=$c; sleep 2s; done; echo


    0
    curl --cookie name=<cookie_value> --data-urlencode name=my_post_key=<post_key>\&delete=1\&submit=Delete+Now\&action=deletepost\&pid=$c --user-agent Firefox\ 3.5 --url http://url/editpost.php?my_post_key=<post_key>\&delete=1\&submit=Delete+Now\&action=dele
    mrlockfs · 2010-07-14 01:50:48 5
  • Change the number to change the number of spaces. Leaving it out defaults to 8. Leaving out the filename defaults to stdin. And to do it in reverse, you can use the unexpand command.


    -1
    expand -t 2 <filename>
    camocrazed · 2010-07-13 23:04:57 3
  • Thanks th John_W for suggesting the fix allowing ~/ to be used when saving a directory. directions: Type in a url, it will show a preview of what the file will look like when saved, then asks if you want to save the preview and where you want to save it. Great for grabbing the latest commandlinefu commands without a full web browser or even a GUI. Requires: w3m Show Sample Output


    0
    read -p "enter url:" a ; w3m -dump $a > /dev/shm/e1q ; less /dev/shm/e1q ; read -p "save file as text (y/n)?" b ; if [ $b = "y" ] ; then read -p "enter path with filename:" c && touch $(eval echo "$c") ; mv /dev/shm/e1q $(eval echo "$c") ; fi ; echo DONE
    LinuxMan · 2010-07-13 22:36:38 5
  • Same as another one I saw, just with a cleaner sed command Edit: updated the sed command to use the [[:xdigit:]] character class - more portable between locales Note that it will have a newline inserted after every 32 characters of input, due to the output of xxd Show Sample Output


    0
    echo -n 'text' | xxd -ps | sed 's/[[:xdigit:]]\{2\}/\\x&/g'
    camocrazed · 2010-07-13 21:46:30 3
  • Lists a sample of all installed toilet fonts Show Sample Output


    3
    find /usr/share/figlet -name *.?lf -exec basename {} \; | sed -e "s/\..lf$//" | xargs -I{} toilet -f {} {}
    unixmonkey3987 · 2010-07-13 20:12:54 5
  • [ 2000 -ge "$(free -m | awk '/buffers.cache:/ {print $4}')" ] returns true if less than 2000 MB of RAM are available, so adjust this number to your needs. [ $(echo "$(uptime | awk '{print $10}' | sed -e 's/,$//' -e 's/,/./') >= $(grep -c ^processor /proc/cpuinfo)" | bc) -eq 1 ] returns true if the current machine load is at least equal to the number of CPUs. If either of the tests returns true we wait 10 seconds and check again. If both tests return false, i.e. 2GB are available and machine load falls below number of CPUs, we start our command and save it's output in a text file. The ( ( ... ) & ) construct lets the command run in background even if we log out. See http://www.commandlinefu.com/commands/view/3115/ .


    4
    ( ( while [ 2000 -ge "$(free -m | awk '/buffers.cache:/ {print $4}')" ] || [ $(echo "$(uptime | awk '{print $10}' | sed -e 's/,$//' -e 's/,/./') >= $(grep -c ^processor /proc/cpuinfo)" | bc) -eq 1 ]; do sleep 10; done; my-command > output.txt ) & )
    michelsberg · 2010-07-13 09:12:11 3
  • this command shows the space used in postgres directory. Show Sample Output


    -5
    while (( 1==1 )); do du -c . >> output.log; sleep 2; done; tail -f output.log
    aceiro · 2010-07-12 17:23:45 4
  • Full Command: google contacts list name,name,email|perl -pne 's%^((?!N\/A)(.+?)),((?!N\/A)(.+?)),([a-z0-9\._-]+\@([a-z0-9][a-z0-9-]*[a-z0-9]\.)+([a-z]+\.)?([a-z]+))%${1}:${3} <${5}>%imx'|grep -oP '^((?!N\/A)(.+?)) <[a-z0-9\._-]+\@([a-z0-9][a-z0-9-]*[a-z0-9]\.)+([a-z]+\.)?([a-z]+)>' | sort You'll need googlecl and python-gdata. First setup google cl via: google Then give your PC access google contacts list name,email Then do the command, save it or use this one to dump it in the cone-address.txt file in your home dir: google contacts list name,name,email | perl -p -n -e 's%^((?!N\/A)(.+?)),((?!N\/A)(.+?)),([a-z0-9\._-]+\@([a-z0-9][a-z0-9-]*[a-z0-9]\.)+([a-z]+\.)?([a-z]+))%${1}:${3} <${5}>%imx' | grep -o -P '^((?!N\/A)(.+?)) <[a-z0-9\._-]+\@([a-z0-9][a-z0-9-]*[a-z0-9]\.)+([a-z]+\.)?([a-z]+)>' | sort > ~/cone-adress.txt Then import into cone. It filters out multiple emails, and contacts with no email that have N/A. (Picasa photo persons without email for example...) Show Sample Output


    1
    google contacts list name,name,email|perl -pne 's%^((?!N\/A)(.+?)),((?!N\/A)(.+?)),([a-z0-9\._-]+\@([a-z0-9][a-z0-9-]*[a-z0-9]\.)+([a-z]+\.)?([a-z]+))%${1}:${3} <${5}>%imx' #see below for full command
    Raymii · 2010-07-12 16:50:44 148

  • -1
    wget --load-cookies <cookie-file> -c -i <list-of-urls>
    alriode · 2010-07-12 02:35:21 3
  • I have this as a file called deletekey in my ~/bin. Makes life a little easier.


    -13
    echo "${1}" | egrep '^[[:digit:]]*$' ; if [ "$?" -eq 0 ] ; then sed -i "${1}"d $HOME/.ssh/known_hosts ; else printf "\tYou must enter a number!\n\n" ; exit 1 ; fi
    DaveQB · 2010-07-11 23:09:11 3
  • In this case it's better do to use the dedicated tool


    45
    ssh-keygen -R <the_offending_host>
    bunam · 2010-07-11 19:37:24 16
  • Disable randomisation address Show Sample Output


    -1
    echo 0 > /proc/sys/kernel/randomize_va_space
    gunslinger_ · 2010-07-11 16:42:42 3
  • sending packet by ping if sending more high packet root needed... Show Sample Output


    -3
    sudo ping -f -c 999 -s 4500 target.com
    gunslinger_ · 2010-07-11 16:38:44 13
  • Print "Art of hacking..." 100 times by perl or you can this tools : http://packetstormsecurity.org/shellcode/shellcodeencdec.py.txt Show Sample Output


    -15
    perl -e 'print "\x41\x72\x74\x20\x6f\x66\x20\x68\x61\x63\x6b\x69\x6e\x67\x2e\x2e\x2e\n" x 100'
    gunslinger_ · 2010-07-11 16:32:00 7
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Convert a bunch of HTML files from ISO-8859-1 to UTF-8 file encoding in a folder and all sub-folders
This is my first attempt at converting all HTML files to UTF-8 file encoding, including all subfolders. Theres probably a much more compact way to do it, but I'm quite proud of it with my windows background ;)

Ping all hosts on 192.168.1.0/24
-b option takes the broadcast address.

Lines per second in a log file
Another way of counting the line output of tail over 10s not requiring pv. Cut to have the average per second rate : tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log | cut -c-2 You can also enclose it in a loop and send stderr to /dev/null : while true; do tail -n0 -f access.log>/tmp/tmp.log & sleep 2; kill $! ; wc -l /tmp/tmp.log | cut -c-2; done 2>/dev/null

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

display typedefs, structs, unions and functions provided by a header file
will display typedefs, structs, unions and functions declared in 'stdio.h'(checkout _IO_FILE structure). It will be helpful if we want to know what a particular header file will offer to us. Command 'cpp' is GNU's C Preprocessor.

Transform a portrait pdf in a landscape one with 2 pages per page
This is an example of the usage of pdfnup (you can find it in the 'pdfjam' package). With this command you can save ink/toner and paper (and thus trees!) when you print a pdf. This tools are very configurable, and you can make also 2x2, 3x2, 2x3 layouts, and more (the limit is your fantasy and the resolution of the printer :-) You must have installed pdfjam, pdflatex, and the LaTeX pdfpages package in your box.

Produce a pseudo random password with given length in base 64

Merge several pdf files into a single file
merge a.pdf b.pdf and c.pdf and create ./out.pdf

Watch Star Wars via telnet
Use Ctrl-] to stop it.

Port Knocking!
Knock on ports to open a port to a service (ssh for example) and knock again to close the port. You have to install knockd. See example config file below. [options] logfile = /var/log/knockd.log [openSSH] sequence = 3000,4000,5000 seq_timeout = 5 command = /sbin/iptables -A INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn [closeSSH] sequence = 5000,4000,3000 seq_timeout = 5 command = /sbin/iptables -D INPUT -i eth0 -s %IP% -p tcp --dport 22 -j ACCEPT tcpflags = syn


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