Commands using printf (171)


  • 0
    /sbin/ifconfig |awk '/bond|eth/{getline i;printf $0" ";printf "%s\n", i" "}'|awk '{print $1,substr($7,6)}'
    omatictost · 2012-10-25 16:08:15 0
  • Counts the files present in the different directories recursively. One only has to change maxdepth to have further insight in the directory hierarchy. Found at unix.stackexchange.com: http://unix.stackexchange.com/questions/4105/how-do-i-count-all-the-files-recursively-through-directories Show Sample Output


    1
    find -maxdepth 3 -type d | while read -r dir; do printf "%s:\t" "$dir"; find "$dir" | wc -l; done
    brainstorm · 2012-10-15 15:00:09 1
  • Prints 0's and 1's in The Matrix style. You can easily modify to print 0-9 digits using $RANDOM %10 insted of %2.


    4
    echo -e "\e[32m"; while :; do printf '%*c' $(($RANDOM % 30)) $(($RANDOM % 2)); done
    fernandomerces · 2012-09-25 17:36:25 0
  • This command will find the highest context switches on a server and give you the process listing. Show Sample Output


    0
    grep -H voluntary_ctxt /proc/*/status |gawk '{ split($1,proc,"/"); if ( $2 > 10000000 ) { printf $2 " - Process : "; system("ps h -o cmd -p "proc[3]) } }' | sort -nk1,1 | sed 's/^/Context Switches: /g'
    jperkster · 2012-09-01 19:43:47 0
  • Could easily be used for lowercase --> ((i=97;i Show Sample Output


    0
    for ((i=65;i<91;i++)); do printf "\\$(printf '%03o' $i) "; done
    slappy · 2012-08-24 13:24:36 0
  • usage: alarmclock TIME TIME is a sleep(1) parameter which tells function how long to wait until raise the alarm.


    0
    alarmclock() { [ $1 ] || echo Parameter TIME is missing. 1>&2 && return 1 ; ( sleep $1 ; for x in 9 8 7 6 5 4 3 2 1 ; do for y in `seq 0 $[ 10 - $x ] ` ; do printf "\a"; sleep 0.$x ; done ; done ) & }
    lkj · 2012-08-16 15:35:15 0
  • printf reapeats the format as longer as it has arguments. Then the idea is to make cut retain as much fields as we have elements in the array. As usual with such join/split string manipulation, you have to make sure you don't have conflicts between your separator and your array content.


    0
    printf "%s," "${LIST[@]}" | cut -d "," -f 1-${#LIST[@]}
    Valise · 2012-06-04 14:56:12 0
  • Sometimes you want to see all of the systcls for a given $thing. I happened to need to easily look at all of the vm sysctls between two boxes and compare them. This is what I came up with. Show Sample Output


    0
    find /proc/sys/vm -maxdepth 1 -type f | while read i ; do printf "%-35s\t%s\n" "$i" "$(<$i)" ; done | sort -t/ -k4
    SEJeff · 2012-05-25 16:34:16 0
  • 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 0
  • Use tput cols to find the width of the terminal and set it as the minimum field width. Show Sample Output


    9
    printf "%$(tput cols)s\n"|tr ' ' '='
    webstandardcss · 2012-04-21 23:26:55 1

  • 0
    yes "$(seq 232 255;seq 254 -1 233)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done
    hogofogo · 2012-04-03 06:41:43 0
  • proc lister usage: p proc killer usage: p patt [signal] uses only ps, grep, sed, printf and kill no need for pgrep/pkill (not part of early UNIX) _p(){ ps ax \ |grep $1 \ |sed ' /grep.'"$1"'/d' \ |while read a;do printf ${a%% *}' '; printf "${a#* }" >&2; printf '\n'; done; } p(){ case $# in 0) ps ax |grep .|less -iE; ;; 1) _p $1; ;; [23]) _p $1 2>/dev/null \ |sed '/'"$2"'/!d; s,.*,kill -'"${3-15}"' &,'|sh -v ;; esac; } alas, can't get this under 255 chars. flatcap? Show Sample Output


    0
    _p(){ ps ax |grep $1 |sed '/grep.'"$1"'/d' |while read a;do printf ${a%% *}' ';printf "${a#* }" >&2;printf '\n';done;}
    argv · 2012-04-01 19:46:19 1
  • proc lister usage: p proc killer usage: p patt [signal] uses only ps, grep, sed, printf and kill no need for pgrep/pkill (not part of early UNIX) _p(){ ps ax \ |grep $1 \ |sed ' /grep.'"$1"'/d' \ |while read a;do printf ${a%% *}' '; printf "${a#* }" >&2; printf '\n'; done; } p(){ case $# in 0) ps ax |grep .|less -iE; ;; 1) _p $1; ;; [23]) _p $1 2>/dev/null \ |sed '/'"$2"'/!d; s,.*,kill -'"${3-15}"' &,'|sh -v ;; esac; } alas, can't get this under 255 chars. flatcap? Show Sample Output


    0
    _p(){ ps ax |grep $1 |sed '/grep.'"$1"'/d' |while read a;do printf ${a%% *}' ';printf "${a#* }" >&2;printf '\n';done;}
    argv · 2012-04-01 19:45:17 0
  • Improvement on Coderjoe's Solution. Gets rid of grep and cut (and implements them in awk) and specifies some different mplayer options that speed things up a bit. Show Sample Output


    0
    find /path/to/dir -iname "*.ext" -print0 | xargs -0 mplayer -really-quiet -cache 64 -vo dummy -ao dummy -identify 2>/dev/null | awk '/ID_LENGTH/{gsub(/ID_LENGTH=/,"")}{SUM += $1}END{ printf "%02d:%02d:%02d\n",SUM/3600,SUM%3600/60,SUM%60}'
    DarkSniper · 2012-03-11 12:28:48 0
  • This one line Perl script will display the smallest to the largest files sizes in all directories on a server. Show Sample Output


    1
    du -k | sort -n | perl -ne 'if ( /^(\d+)\s+(.*$)/){$l=log($1+.1);$m=int($l/log(1024)); printf ("%6.1f\t%s\t%25s %s\n",($1/(2**(10*$m))),(("K","M","G","T","P")[$m]),"*"x (1.5*$l),$2);}' | more
    Q_Element · 2012-02-07 15:49:19 0
  • 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 0
  • You can use ordinary printf to convert "%23%21%2fbin%2fbash" into "#!/bin/bash" with no external utilities, by using a little known printf feature -- the "%b" specifier converts shell escapes. Replace % with \x and printf will understand the urlencoded string. BASH's printf has an extension to set a variable directly, too. So you get to convert urlencoded strings from garble to plaintext in one step with no externals and no backticks. Show Sample Output


    5
    VAR="%23%21%2fbin%2fbash" ; printf -v VAR "%b" "${VAR//\%/\x}" ; echo $VAR
    Corona688 · 2012-01-06 22:09:01 3
  • List the full path of some files. You can add ".*" on the end if you want to display hidden files. Show Sample Output


    3
    printf "$PWD/%s\n" *
    flatcap · 2011-12-16 13:43:01 1

  • 7
    hex() { printf "%X\n" $1; }
    4Aiur · 2011-12-13 04:45:21 0
  • Better awk example, using only mplayer, grep, cut, and awk. Show Sample Output


    0
    mplayer -endpos 0.1 -vo null -ao null -identify *.avi 2>&1 |grep ID_LENGTH |cut -d = -f 2|awk '{SUM += $1} END { printf "%d:%d:%d\n",SUM/3600,SUM%3600/60,SUM%60}'
    Coderjoe · 2011-12-12 15:49:07 0
  • Parses /etc/group to "dot" format and pases it to "display" (imagemagick) to show a usefull diagram of users and groups (don't show empty groups).


    19
    awk 'BEGIN{FS=":"; print "digraph{"}{split($4, a, ","); for (i in a) printf "\"%s\" [shape=box]\n\"%s\" -> \"%s\"\n", $1, a[i], $1}END{print "}"}' /etc/group|display
    point_to_null · 2011-12-04 01:56:44 1
  • Converts a number of bytes provided as input, to a human readable number. Show Sample Output


    2
    human_filesize() { awk -v sum="$1" ' BEGIN {hum[1024^3]="Gb"; hum[1024^2]="Mb"; hum[1024]="Kb"; for (x=1024^3; x>=1024; x/=1024) { if (sum>=x) { printf "%.2f %s\n",sum/x,hum[x]; break; } } if (sum<1024) print "1kb"; } '}
    ArtBIT · 2011-12-02 18:21:20 0
  • Converts IP octets to hex using printf command. Useful for generating pxeboot aliases in the pxelinux.cfg folder. Show Sample Output


    2
    myhex=$(printf '%02X' ${myip//./ };)
    robinsonaarond · 2011-11-30 15:12:28 0

  • 0
    find . -type f -exec awk '/linux/ { printf "%s %s: %s\n",FILENAME,NR,$0; }' {} \;
    Neo23x0 · 2011-11-29 12:32:06 1
  • poorman's ifstat using just sh and awk. You must change "eth0" with your interface's name. Show Sample Output


    10
    while true; do cat /proc/net/dev; sleep 1; done | awk -v dc="date \"+%T\"" '/eth0/{i = $2 - oi; o = $10 - oo; oi = $2; oo = $10; dc|getline d; close(dc); if (a++) printf "%s %8.2f KiB/s in %8.2f KiB/s out\n", d, i/1024, o/1024}'
    point_to_null · 2011-11-21 05:24:44 8
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