Commands using printf (206)

  • Uses soxi instead of mplayer


    0
    soxi -D * | awk '{SUM += $1} END { printf "%d:%d:%d\n",SUM/3600,SUM%3600/60,SUM%60}'
    hufman · 2017-04-08 17:37:03 15
  • All the other example fail when running in a folder containing too many files due to * being saturated. This command does not use *, allowing me to run it in one folder containing over 300000 audio files. As to running on so many files, I used GNU parallel in order to spawn as many processes as cores, tremendously fasting up the process. Show Sample Output


    0
    ls|grep ".wav"|parallel -j$(nproc) soxi -D {}|awk '{SUM += $1} END { printf "%d:%d:%d\n",SUM/3600,SUM%3600/60,SUM%60}'
    jupiter126 · 2017-05-02 21:37:24 20
  • Prints the variable "$a" 80 times with a new line at the end. There is no need for backspaces as printf (by default) does not print a newline nor an space. Use a bunch of variables called "$_0" and a number. The name start with an underscore and a 0 to avoid conflicts with already defined variables. If still worried: All variables may be cleared up before use with "unset $_{1..080}". A command with a variable count is a bit of a mouthful: a=hello+; n=7; eval printf "%s" '$_{1..0'"$n"'}"$a"' $'$\'\\n\'' And carry some risk if the variable "$n" could be set by an attacker. Show Sample Output


    0
    a=+; printf "%s" $_{1..080}"$a" $'\n'
    isaacmarcos · 2017-06-06 21:59:58 17
  • This is a bit of a bash hack to catch STDERR and append a log level to it. So for example, if your script has pseudo loglevels like so: echo "INFO - finding files" [ -f ${files} ] || echo "WARN - no files found" Any subcommands that write to STDERR will screw that up Adding 2> >(fb=$(dd bs=1 count=1 2>/dev/null | od -t o1 -A n); [ "$fb" ] && err=$(printf "\\${fb# }"; cat) && echo "ERROR - $err") to the command does the following: 2> Redirect STDERR >( Spawn a subshell (STDERR is then redirected to the file descriptor for this subshell) fb=$(....) get the first byte of input [ "$fb" ] test if there's a first byte && err=$(printf....) save the output to the $err variable && echo "ERROR - $err" append your pseudo loglevel and the error message Heavily borrowed from https://unix.stackexchange.com/questions/33049/check-if-pipe-is-empty-and-run-a-command-on-the-data-if-it-isnt Show Sample Output


    0
    [command] 2> >(fb=$(dd bs=1 count=1 2>/dev/null | od -t o1 -A n); [ "$fb" ] && err=$(printf "\\${fb# }"; cat) && echo "ERROR - $err")
    tyzbit · 2017-10-16 22:22:42 21
  • Compactly display a bitcoin-cli fee estimate in satoshis/Byte, sat/B, date time stamp. Change the 6 to the desired number of confirmations. Display in btc/KB unit of measure: printf %g "$(bccli estimatesmartfee 6 "ECONOMICAL" | jq .feerate)";printf " btc/KB estimated feerate for 6 confirmations\nMultiply by 100,000 to get sat/B\n"; Two settings for estimate mode are "ECONOMICAL". "CONSERVATIVE" is the same as "UNSET" # jq is a json filter. sudo apt-get install jq Show Sample Output


    0
    printf %g "$(bitcoin-cli estimatesmartfee 6 "ECONOMICAL" | jq .feerate*100000)";printf " sat/B estimated feerate for 6 confirmations as of $(date +%c)\nDivide by 100,000 to get btc/KB\n"
    deinerson1 · 2018-06-20 13:40:32 242
  • Use this function with bash version 4+ to convert arbitrary hexadecimal sequences to binary. If you don't have bash 4+ then modify the lowercase to uppercase demangling statement s=${@^^} to set s equal to the uppercase hex input or the bc command throws an input parser error. Show Sample Output


    0
    hex2bin () { s=${@^^}; for i in $(seq 0 1 $((${#s}-1))); do printf "%04s" `printf "ibase=16; obase=2; ${s:$i:1};\n" | bc` ; done; printf "\n"; }
    RiskNerd · 2018-10-02 22:02:33 351

  • 0
    printf %s\\n '"\en": "\e0\e."' '"\em": "\e1\e."' '"\e,": "\e2\e."'>>~/.inputrc
    lri · 2019-01-22 07:10:16 32
  • This shell calculator uses POSIX features only and is therefore portable. By default the number of significant figures is limited to 8 with trailing zeros stripped, resembling the display of a basic pocket calculator. You might want to increase this to 12 to emulate a scientific calculator. Show Sample Output


    0
    calc(){ printf "%.8g\n" $(printf "%s\n" "$*" | bc -l); }
    lordtoran · 2019-02-06 23:32:35 607
  • No need to fork off a process.


    0
    printf "%.s*" {1..40}; printf "\n"
    doododoltala · 2019-07-11 00:27:20 37
  • This “sysload” alias converts the load average to percentages and divides them by the number of CPUs/cores. It may provide a more intuitive guesstimate of how much work the server is doing. Show Sample Output


    0
    alias sysload='printf "System load (1m/5m/15m): "; for l in 1 2 3 ; do printf "%.1f%s" "$(( $(cat /proc/loadavg | cut -f $l -d " ") * 100 / $(nproc) ))" "% "; done; printf "\n"'
    lordtoran · 2021-03-27 17:10:53 152
  • Show temp of all disk with the drivetemp module activate Show Sample Output


    0
    grep -l "drivetemp" /sys/class/hwmon/hwmon*/name | while read f; do printf "%s(%-.2s°C)\n" "`<${f%/*}/device/model`" "`<${f%/*}/temp1_input`"; done
    kokoparkletal · 2023-09-10 18:24:29 80
  • This command adds the numbers 10, 12, 14 to a bunch of mp3's in the current working directory. You can then run the command replacing the inital i=10 with i=11 to add 11,13,15 in another directory then mv the files together and the first files interweave with the second group of files. I used this to weave a backlog of a podcast with other podcast so I didn't get sick of one while I was catching up. I started at 10 because printf blows up with 0 padded numbers 08 and 09 which kind of makes the printf command redundant as it was used to pad numbers 1 - 9 so they would come first and not get sorted incorrectly


    -1
    i=10;for o in *.mp3; do i=$(printf "%02d" $i); mv $o $i$o; ((i = $i + 2)); done
    bazzawill · 2009-04-13 12:33:52 7
  • There's no need for ls or grep; printf is builtin to most modern shells


    -1
    printf "%s\n" !(pattern) ## ksh, or bash with shopt -s extglob
    cfajohnson · 2009-11-26 14:09:56 3
  • So your boss wants to know how much memory has been assigned to each virtual machine running on your server... here's how to nab that information from the command line while logged in to that server Show Sample Output


    -1
    for file in $( vmrun list | grep 'vmx$' | sort ); do printf "% 40s %s M\n" $(echo "$( echo -n ${file}:\ ; grep memsize $file )" | sed -e 's/.*\///' -e 's/"//g' -e 's/memsize.=//'); done;
    linuxrawkstar · 2010-11-19 06:14:11 3
  • remove all carriage return of a given file (or input, if used with | ) and replace them with a space (or whatever character is after %s) Show Sample Output


    -1
    awk ' { printf ("%s ", $0)} END {printf ("\n") } ' FILE
    bouktin · 2011-02-02 11:51:41 6
  • The exported TSV file of Google Adwords' first five columns are text, they usually should collapse into one cell, a multi-line text cell, but there is no guaranteed way to represent line-break within cells for .tsv file format, thus Google split it to 5 columns. The problem is, with 5 columns of text, there are hardly space to put additional fields while maintain printable output. This script collapses the first five columns of each row into one single multi-line text cell, for console output or direct send to printer.


    -1
    awk -F $'\t' '{printf $1 LS $2 LS $3 LS $4 LS $5; for (i = 7; i < NF; i++) printf $i "\t"; printf "\n--\n";}' LS=$'\n' 'Ad report.tsv' | column -t -s $'\t'
    zhangweiwu · 2011-02-28 10:52:16 4
  • This command will delete all branches in your git repository other than next and master. I use this to cleanup my git repos after making multiple branches and merging them back into next. It's much faster than individually deleting each expired branch using: git branch -D <branch_name>


    -1
    git branch -D `git branch | awk '{ if ($0 !~ /next|master/) printf "%s", $0 }'`
    denheck · 2011-04-14 17:43:21 4
  • Group membership in OS X is a mish-mash of standards that end up meaning there's almost a half-dozen of ways to belong to a group, what with group inheritance and automatic assignment. This means there's no easy command to find out all groups a user belongs to. The only sensible way then is to list all users and then query each user for membership. NOTE: This is a function. Once input you can execute it by calling with a groupname. Show Sample Output


    -1
    members () { dscl . -list /Users | while read user; do printf "$user "; dsmemberutil checkmembership -U "$user" -G "$*"; done | grep "is a member" | cut -d " " -f 1; };
    eduo · 2012-05-20 11:34:33 7
  • I don't think it's possible to give a (background) colour to the tab itself, since a tab is, IIUC, simply a command to the terminal to move to the right. Nevertheless, this "highlighting" can be helpful when working with tab-separated files. Show Sample Output


    -1
    hl-nonprinting () { local C=$(printf '\033[0;36m') R=$(printf '\033[0m'); sed -e "s/\t/${C}&#9657;&$R/g" -e "s/$/${C}&#8267;$R/";}
    unhammer · 2012-11-07 09:55:48 4
  • Can't see it here, but the non-breaking space is highlighted :) Of course, cat -t -e achieves something similar, but less colourful. Could add more code points from https://en.wikipedia.org/wiki/Space_%28punctuation%29#Spaces_in_Unicode Show Sample Output


    -1
    hl-nonprinting () { local C=$(printf '\033[0;36m') B=$(printf '\033[0;46m') R=$(printf '\033[0m') np=$(env printf "\u00A0\uFEFF"); sed -e "s/\t/${C}&#9657;&$R/g" -e "s/$/${C}&#8267;$R/" -e "s/[$np]/${B}& $R/g";}
    unhammer · 2012-11-07 10:09:40 9

  • -1
    yes 'c=(" " " " " " 0 1); printf "${c[RANDOM%5]}"' | bash
    stx · 2013-11-09 16:10:41 6
  • Needs to be run in a battery sysfs dir, eg. /sys/class/power_supply/BAT0 on my system. Displays the battery's current charge and the rate per-second at which energy is {dis,}charging. All values are displayed as percentages of "full" charge. The first column is the current charge. The second is the rate of change averaged over the entire lifetime of the command (or since the AC cable was {un,}plugged), and the third column is the rate of change averaged over the last minute (controlled by the C=60 variable passed to awk). The sample output captures a scenario where I ran 'yes' in another terminal to max out a CPU. My battery was at 76% charge and you can see the energy drain starts to rise above 0.01% per-second as the cpu starts working and the fan kicks in etc. While idle it was more like 0.005% per-second. I tried to use this to estimate the remaining battery life/time until fully charged, but found it to be pretty useless... As my battery gets more charged it starts to charge slower, which meant the estimate was always wrong. Not sure if that's common for batteries or not. Show Sample Output


    -1
    while cat energy_now; do sleep 1; done |awk -v F=$(cat energy_full) -v C=60 'NR==1{P=B=$1;p=100/F} {d=$1-P; if(d!=0&&d*D<=0){D=d;n=1;A[0]=B=P}; if(n>0){r=g=($1-B)/n;if(n>C){r=($1-A[n%C])/C}}; A[n++%C]=P=$1; printf "%3d %+09.5f %+09.5f\n", p*$1, p*g, p*r}'
    sqweek · 2015-09-19 15:45:40 11
  • Better -and faster- using bash printf. Show Sample Output


    -2
    printf "%50s\n"|tr ' ' -
    rodolfoap · 2010-01-07 08:49:46 6

  • -2
    printf "%d\n" \0x64
    4Aiur · 2010-01-09 02:50:50 3

  • -2
    printf "%.50d" 0 | tr 0 -
    sata · 2010-03-25 12:52:45 3
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tar directory and compress it with showing progress and Disk IO limits
tar directory and compress it with showing progress and Disk IO limits. Pipe Viewer can be used to view the progress of the task, Besides, he can limit the disk IO, especially useful for running Servers.

Convert multiple flac files to mp3
make sure that flac and lame are installed sudo apt-get install lame flac

colorize your svn diff
Will colorize your svn diff.

Do quick arithmetic on numbers from STDIN with any formatting using a perl one liner.
Good for summing the numbers embedded in text - a food journal entry for example with calories listed per food where you want the total calories. Use this to monitor and keep a total on anything that ouputs numbers.

Create the four oauth keys required for a Twitter stream feed
Twitter stream feeds now require authentication. This command is the FIRST in a set of five commands you'll need to get Twitter authorization for your final Twitter command. *** IMPORTANT *** Before you start, you have to get some authorization info for your "app" from Twitter. Carefully follow the instructions below: Go to dev.twitter.com/apps and choose "Create a new application". Fill in the form. You can pick any name for your app. After submitting, click on "Create my access token". Keep the resulting page open, as you'll need information from it below. If you closed the page, or want to get back to it in the future, just go to dev.twitter.com/apps Now customize FIVE THINGS on the command line as follows: 1. Replace the string "Consumer key" by copying & pasting your custom consumer key from the Twitter apps page. 2. Replace the string "Consumer secret" by copying & pasting your consumer secret from the Twitter apps page. 3. Replace the string "Access token" by copying & pasting your access token from the Twitter apps page. 4. Replace string "Access token secret" by copying & pasting your own token secret from the Twitter apps page. 5. Replace the string 19258798 with the Twitter UserID NUMBER (this is **NOT** the normal Twitter NAME of the user you want the tweet feed from. If you don't know the UserID number, head over to www.idfromuser.com and type in the user's regular Twitter name. The site will return their Twitter UserID number to you. 19258798 is the Twitter UserID for commandlinefu, so if you don't change that, you'll receive commandlinefu tweets, uhm... on the commandline :) Congratulations! You're done creating all the keys! Environment variables k1, k2, k3, and k4 now hold the four Twitter keys you will need for your next step. The variables should really have been named better, e.g. "Consumer_key", but in later commands the 256-character limit forced me to use short, unclear names here. Just remember k stands for "key". Again, remember, you can always review your requested Twitter keys at dev.twitter.com/apps. Our command line also creates four additional environment variables that are needed in the oauth process: "once", "ts", "hmac" and "id". "once" is a random number used only once that is part of the oauth procedure. HMAC is the actual key that will be used later for signing the base string. "ts" is a timestamp in the Posix time format. The last variable (id) is the user id number of the Twitter user you want to get feeds from. Note that id is ***NOT*** the twitter name, if you didn't know that, see www.idfromuser.com If you want to learn more about oauth authentication, visit oauth.net and/or go to dev.twitter.com/apps, click on any of your apps and then click on "Oauth tool" Now go look at my next command, i.e. step2, to see what happens next to these eight variables.

Remove BOM (Byte Order Mark) from text file
Takes file (text.txt), removes BOM from it, and outputs the result to a new file (newFile.txt). BOM is "Byte Order Mark" ([http://en.wikipedia.org/wiki/Byte_order_mark]), an invisible, non-breaking, zero-length character. In other words, if you see a DIFF with "" at the beginning, you've got a byte order mark, which can't be removed without this command or a hex editor. It can appear for a number of reasons, such as getting copied to/from a UNIX filesystem...

echo unicode characters

Start a quick rsync daemon for fast copying on internal secure network
"Sample output" shows a minimalistic configuration file.

Mount directories in different locations
Like symlinked directories, you can mount a directory at a different location. For example mounting a directory from one location in to the http root without having to make your program follow symlinks or change permissions when reading.

Find the package that installed a command


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