Commands tagged for loop (28)

  • A bitcoin "brainwallet" is a secret passphrase you carry in your brain. The Bitcoin Brainwallet Private Key Base58 Encoder is the third of three functions needed to calculate a bitcoin PRIVATE key from your "brainwallet" passphrase. This base58 encoder uses the obase parameter of the amazing bc utility to convert from ASCII-hex to base58. Tech note: bc inserts line continuation backslashes, but the "read s" command automatically strips them out. I hope that one day base58 will, like base64, be added to the amazing openssl utility. Show Sample Output


    6
    function b58encode () { local b58_lookup_table=({1..9} {A..H} {J..N} {P..Z} {a..k} {m..z}); bc<<<"obase=58;ibase=16;${1^^}"|(read -a s; for b58_index in "${s[@]}" ; do printf %s ${b58_lookup_table[ 10#"$b58_index" ]}; done); }
    nixnax · 2014-02-18 02:29:30 13
  • Each file in the current folder is uploaded to imageshack.us If the folder contains other filetypes change: for files in * to: for files in *.jpg (to upload ONLY .jpg files) Additionally you can try (results may vary): for files in *.jpg *.png The output URL is encased with BB image tags for use in a forum. Show Sample Output


    4
    imageshack() { for files in *; do curl -H Expect: -F fileupload="@$files" -F xml=yes -# "http://www.imageshack.us/index.php" | grep image_link | sed -e 's/<image_link>/[IMG]/g' -e 's/<\/image_link>/[\/IMG]/g'; done; }
    operatinghazard · 2010-10-01 06:50:04 6
  • This uses some tricks I found while reading the bash man page to enumerate and display all the current environment variables, including those not listed by the 'env' command which according to the bash docs are more for internal use by BASH. The main trick is the way bash will list all environment variable names when performing expansion on ${!A*}. Then the eval builtin makes it work in a loop. I created a function for this and use it instead of env. (by aliasing env). This is the function that given any parameters lists the variables that start with it. So 'aae B' would list all env variables starting wit B. And 'aae {A..Z} {a..z}' would list all variables starting with any letter of the alphabet. And 'aae TERM' would list all variables starting with TERM. aae(){ local __a __i __z;for __a in "$@";do __z=\${!${__a}*};for __i in `eval echo "${__z}"`;do echo -e "$__i: ${!__i}";done;done; } And my printenv replacement is: alias env='aae {A..Z} {a..z} "_"|sort|cat -v 2>&1 | sed "s/\\^\\[/\\\\033/g"' From: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    2
    for _a in {A..Z} {a..z};do _z=\${!${_a}*};for _i in `eval echo "${_z}"`;do echo -e "$_i: ${!_i}";done;done|cat -Tsv
    AskApache · 2010-10-27 07:16:54 5
  • Change the $domain variable to whichever domain you wish to query. Works with the majority of whois info; for some that won't, you may have to compromise: domain=google.com; for a in $(whois $domain | grep "Domain servers in listed order:" --after 3 | grep -v "Domain servers in listed order:"); do echo ">>> Nameservers for $domain from $a Note that this doesn't work as well as the first one; if they have more than 3 nameservers, it won't hit them all. As the summary states, this can be useful for making sure the whois nameservers for a domain match the nameserver records (NS records) from the nameservers themselves. Show Sample Output


    2
    domain=google.com; for ns in $(whois $domain | awk -F: '/Name Server/{print $2}'); do echo ">>> Nameservers for $domain from $a <<<"; dig @$ns $domain ns +short; echo; done;
    laebshade · 2011-05-08 04:46:34 4
  • Applies each file operator using the built-in test. testt /home/askapache/.sq /home/askapache/.sq -a True - file exists. -d True - file is a directory. -e True - file exists. -r True - file is readable by you. -s True - file exists and is not empty. -w True - the file is writable by you. -x True - the file is executable by you. -O True - the file is effectively owned by you. -G True - the file is effectively owned by your group. -N True - the file has been modified since it was last read. Full Function: testt () { local dp; until [ -z "${1:-}" ]; do dp="$1"; [[ ! -a "$1" ]] && dp="$PWD/$dp"; command ls -w $((${COLUMNS:-80}-20)) -lA --color=tty -d "$dp"; [[ -d "$dp" ]] && find "$dp" -mount -depth -wholename "$dp" -printf '%.5m %10M %#15s %#9u %-9g %#5U %-5G %Am/%Ad/%AY %Cm/%Cd/%CY %Tm/%Td/%TY [%Y] %p\n' -a -quit 2> /dev/null; for f in a b c d e f g h L k p r s S t u w x O G N; do test -$f "$dp" && help test | sed "/-$f F/!d" | sed -e 's#^[\t ]*-\([a-zA-Z]\{1\}\) F[A-Z]*[\t ]* True if#-\1 "'$dp'" #g'; done; shift; done } Show Sample Output


    2
    testt(){ o=abcdefghLkprsStuwxOGN;echo $@;for((i=0;i<${#o};i++));do c=${o:$i:1};test -$c $1 && help test | sed "/^ *-$c/!d;1q;s/^[^T]*/-$c /;s/ if/ -/";done; }
    AskApache · 2012-02-21 16:54:53 9
  • This is flatcaps tweaked command to make it work on SLES 11.2


    1
    for i in /var/spool/cron/tabs/*; do echo ${i##*/}; sed 's/^/\t/' $i; echo; done
    harpo · 2012-07-12 08:07:20 4

  • 1
    for i in `seq 1 4096`; do tr -dc A-Za-z0-9 </dev/urandom | head -c8192 > dummy$i.rnd; done
    BoxingOctopus · 2013-11-11 21:27:15 8
  • Using the 'time' command, running this with 'tr' took 28 seconds (and change) each time but using base64 only took 8 seconds (and change). If the file doesn't have to be viewable, pulling straight from urandom with head only took 6 seconds (and change)


    1
    for i in {1..4096}; do base64 /dev/urandom | head -c 8192 > dummy$i.rnd ; done
    pdxdoughnut · 2013-11-12 00:36:10 9
  • Note: %~nI expands %I to a file name only (cf. http://technet.microsoft.com/en-us/library/bb490909.aspx)


    1
    FOR %I IN (*.mp4) DO \Tools\ffmpeg\bin\ffmpeg.exe -i "%I" "%~nI.mpeg"
    tomtom99 · 2013-12-25 16:43:49 5
  • Edit YYYY and MM at the beginning of the command with the year and month you want. Note that `DD=$(printf "%02d" $d)` will pad single digit integers with a leading zero. Substitute `echo $YYYY$MM$DD` at the end of the line with the command you want to launch, for instance script.pl --yyyymmdd $YYYY$MM$DD Also available on GitHub as bash util: https://github.com/fibo/yyyymmdd Show Sample Output


    1
    YYYY=2014; MM=02; for d in $(cal -h $MM $YYYY | grep "^ *[0-9]"); do DD=$(printf "%02d" $d); echo $YYYY$MM$DD; done
    fibo · 2014-02-06 11:31:57 41
  • So, I'm using a CentOS VM in VirtualBox, and created four new disks in the SCSI controller. The VM created the folders: /dev/sda /dev/sdb /dev/sdc /dev/sdd Using a 'for loop' all disks are partitioned for LVM.


    1
    for x in {a..d}; do echo -e "n\np\n\n\n\nt\n8e\nw\n" | fdisk /dev/sd"$x"; done
    jaimerosario · 2015-05-21 12:59:48 10
  • In this case I'm selecting all php files in a dir, then echoing the filename and piping it to ~/temp/errors.txt. Then I'm running my alias for PHPCS (WordPress flags in my alias), then piping the PHPCS output to grep and looking for GET. Then I'm piping that output to the same file as above. This gets a list of files and under each file the GET security errors for that file. Extrapolate this to run any command on any list of files and pipe the output to a file. Remove the >> ~/temp/errors.txt to get output to the screen rather than to a file. Show Sample Output


    1
    for f in *php; do echo $f >> ~/temp/errors.txt; phpcsw $f | grep GET >> ~/temp/errors.txt; done
    topher1kenobe · 2023-04-12 14:17:14 367
  • At times I find that I need to loop through a file where each value that I need to do something with is not on a separate line, but rather separated with a ":" or a ";". In this instance, I create a loop within which I define 'IFS' to be something other than a whitespace character. In this example, I iterate through a file which only has one line, and several fields separated with ":". The counter helps me define how many times I want to repeat the loop.


    0
    while [[ COUNTER -le 10 && IFS=':' ]]; do for LINE in $(cat /tmp/list); do some_command(s) $LINE; done; COUNTER=$((COUNTER+1)); done
    slashdot · 2010-09-01 15:09:59 4
  • Ever need to get some text that is a specific number of characters long? Use this function to easily generate it! Doesn't look pretty, but sure does work for testing purposes! Show Sample Output


    0
    genRandomText() { a=( a b c d e f g h i j k l m n o p q r s t u v w x y z );f=0;for i in $(seq 1 $(($1-1))); do r=$(($RANDOM%26)); if [ "$f" -eq 1 -a $(($r%$i)) -eq 0 ]; then echo -n " ";f=0;continue; else f=1;fi;echo -n ${a[$r]};done;echo"";}
    bbbco · 2012-01-20 21:18:16 4
  • Here's my version. It's a bit lengthy but I prefer it since it's all Bash.


    0
    genRandomText() { x=({a..z}); for(( i=0; i<$1; i++ )); do printf ${x[$((RANDOM%26))]}; done; printf "\n"; }
    uxseven · 2012-01-26 08:19:33 3
  • change the time that you would like to have as print interval and just use it to say whatever you want to Show Sample Output


    0
    sayspeed() { for i in $(seq 1 `echo "$1"|wc -c`); do echo -n "`echo $1 |cut -c ${i}`"; sleep 0.1s; done; echo "";}
    kundan · 2012-02-11 05:51:42 3
  • Show the crontabs of all the users. Show Sample Output


    0
    for i in /var/spool/cron/*; do echo ${i##*/}; sed 's/^/\t/' $i; echo; done
    flatcap · 2012-07-11 13:36:34 8
  • Magic line will extract almost all possible archives from current folder in its own folders. Don't forget to change USER name in sudo command. sed is used to create names for folders from archive names w/o extension. You can test sed expression, used in this command: arg='war.lan.net' ; x=$(echo $arg|sed 's/\(.*\)\..*/\1/') ; echo $x If some archives can't be extracted, install packages: apt-get install p7zip-full p7zip-rar Hope this will save a lot of your time. Enjoy.


    0
    for ARG in * ; do sudo -u USER 7z x -o"$(echo $ARG|sed 's/\(.*\)\..*/\1/')" "$ARG" ; done
    n158 · 2012-12-31 19:47:24 7
  • You can implement a FOR loop to act on one or more files returned from the IN clause. We originally found this in order to GPG decrypt a file using wildcards (where you don't know exactly the entire file name, i.e.: Test_File_??????.txt, where ?????? = the current time in HHMMSS format). Since we won't know the time the file was generated, we need to use wildcards. And as a result of GPG not handling wildcards, this is the perfect solution. Thought I would share this revelation. :-) Show Sample Output


    0
    FOR %%c in (C:\Windows\*.*) DO (echo file %%c)
    jmcclosk · 2013-01-31 15:19:54 10

  • 0
    while true; do curl -vsL -o /dev/null example.com 2>&1 | grep 503 > /dev/null || echo "OK: server is up."; sleep 8; done
    noah · 2013-06-26 15:24:51 6

  • 0
    while curl -dsL example.com 2>&1 | grep 503;do sleep 8;done;echo server up
    emile · 2013-07-10 19:03:25 6

  • 0
    for i in `ip addr show dev eth1 | grep inet | awk '{print $2}' | cut -d/ -f1`; do echo -n $i; echo -en '\t'; host $i | awk '{print $5}'; done
    BoxingOctopus · 2013-09-05 17:50:33 7
  • We will turn off and stop multiple linux services using FOR LOOP. Show Sample Output


    0
    for i in rpcbind nfslock lldpad fcoe rpcidmapd; do service $i stop; chkconfig $i off; done
    prasad · 2014-01-23 05:05:22 14

  • 0
    YYYY=2014; MM=02; for DD in $(cal $MM $YYYY | grep "^ *[0-9]"); do [ ${#DD} = 1 ] && DD=0$DD; echo $YYYY$MM$DD; done
    Dentorman · 2015-11-20 09:37:14 706
  • If you don't have seq, you can use perl.


    -1
    genRandomText() { perl -e '$n=shift; print chr(int(rand(26)) + 97) for 1..$n; print "\n"' $1;}
    putnamhill · 2012-01-21 00:21:20 3
  •  1 2 > 

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Uniquely (sort of) color text so you can see changes
Colorify colors input by converting the text to a number and then performing modulo 7 on it. This resulting number is used as the color escape code. This can be used to color the results of commands with complex outputs (like "482279054165371") so if any of the digits change, there's a good chance the color will change too. I say good chance because there's only 7 unique colors here, so assuming you were watching random numbers, there would be a 6/7 chance that the color would change when the number changed. This should really only be used to help quickly identify when things change, but should not be the only thing relied upon to positively assert that an output has not changed.

list all file extensions in a directory
If your grep doesn't have an -o option, you can use sed instead.

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Download all Red Hat Manuals - A better way by user Flatcap
Let's give Flatcap credit for this elegant solution, instead of leaving it hidden as a comment. Tested on RHEL6 and it works. Nice and clean.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Just run it ;)
;)

pretend to be busy in office to enjoy a cup of coffee
combination of several of the above

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Restrict the bandwidth for the SCP command
the command is obvious, I know, but maybe not everyone knows that using the parameter "-l" you can limit the use of bandwidth command scp. In this example fetch all files from the directory zutaniddu and I copy them locally using only 10 Kbs

Serve current directory tree at http://$HOSTNAME:8000/


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