Commands tagged grep (409)

  • Grep for a named process. Show Sample Output


    -4
    psgrep() { if [ ! -z $1 ]; then echo "Grepping for processes matching $1..." ps aux | grep -i $1 | grep -v grep; else echo "!! Need name to grep for"; fi }
    evenme · 2010-02-27 13:47:28 7
  • Suppose you have 11 marbles, 4 of which are red, the rest being blue. The marbles are indistinguishable, apart from colour. How many different ways are there to arrange the marbles in a line? And how many ways are there to arrange them so that no two red marbles are adjacent? There are simple mathematical solutions to these questions, but it's also possible to generate and count all possibilities directly on the command line, using little more than brace expansion, grep and wc! The answer to the question posed above is that there are 330 ways of arranging the marbles in a line, 70 of which have no two red marbles adjacent. See the sample output. To follow the call to marbles 11 4: after c=''; for i in $(seq $1); do c+='{b,r}'; done;, $c equals {b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r}{b,r} After x=$(eval echo $c), and brace expansion, $x equals bbbbbbbbbbb bbbbbbbbbbr ... rrrrrrrrrrb rrrrrrrrrrr, which is all 2^11 = 2048 strings of 11 b's and r's. After p=''; for i in $(seq $2); do p+='b*r'; done;, $p equals b*rb*rb*rb*r Next, after y=$(grep -wo "${p}b*" Finally, grep -vc 'rr' Show Sample Output


    -4
    marbles () { c=''; for i in $(seq $1); do c+='{b,r}'; done; x=$(eval echo $c); p=''; for i in $(seq $2); do p+='b*r'; done; y=$(grep -wo "${p}b*" <<< $x); wc -l <<< "$y"; grep -vc 'rr' <<< "$y"; }
    quintic · 2010-08-27 23:04:33 3
  • Ok so it's rellay useless line and I sorry for that, furthermore that's nothing optimized at all... At the beginning I didn't managed by using netstat -p to print out which process was handling that open port 4444, I realize at the end I was not root and security restrictions applied ;p It's nevertheless a (good ?) way to see how ps(tree) works, as it acts exactly the same way by reading in /proc So for a specific port, this line returns the calling command line of every thread that handle the associated socket


    -5
    p=$(netstat -nate 2>/dev/null | awk '/LISTEN/ {gsub (/.*:/, "", $4); if ($4 == "4444") {print $8}}'); for i in $(ls /proc/|grep "^[1-9]"); do [[ $(ls -l /proc/$i/fd/|grep socket|sed -e 's|.*\[\(.*\)\]|\1|'|grep $p) ]] && cat /proc/$i/cmdline && echo; done
    j0rn · 2009-04-30 12:39:48 631
  • Tail is much faster than sed, awk because it doesn't check for regular expressions. Show Sample Output


    -5
    tail -n +<N> <file> | head -n 1
    qweqq · 2011-09-30 08:30:30 6

  • -6
    grep -A 3 -i "example" demo_text
    techie · 2013-05-09 08:20:31 5
  • I know how hard it is to find an old command running through all the files because you couldn't remember for your life what it was. Heres the solution!! Grep the history for it. depending on how old the command you can head or tail or if you wanted to search all because you cannot think how long ago it was then miss out the middle part of the command. This is a very easy and effective way to find that command you are looking for.


    -9
    cat .bash_history | tail -100 | grep {command}
    techie · 2013-04-10 10:40:52 8
  • Normally, if you just want to see directories you'd use brianmuckian's command 'ls -d *\', but I ran into problems trying to use that command in my script because there are often multiple directories per line. If you need to script something with directories and want to guarantee that there is only one entry per line, this is the fastest way i know Show Sample Output


    -10
    ls -l | grep ^d | sed 's:.*\ ::g'
    LinuxMan · 2011-08-06 23:52:46 9

  • -10
    grep -r <searchterm> *
    totti · 2012-02-08 11:48:08 7
  • David thanks for that grep inside! here is mine version: psgrep() { case ${1} in ( -E | -e ) local EXTENDED_REGEXP=1 shift 1 ;; *) local EXTENDED_REGEXP=0 ;; esac if [[ -z ${*} ]] then echo "psgrep - grep for process(es) by keyword" >&2 echo "Usage: psgrep [-E|-e] ... " >&2 echo "" >&2 echo "option [-E|-e] enables full extended regexp support" >&2 echo "without [-E|-e] plain strings are looked for" >&2 return 1 fi \ps -eo 'user,pid,pcpu,command' w | head -n1 local ARG='' if (( ${EXTENDED_REGEXP} == 0 )) then while (( ${#} > 0 )) do ARG="${1}" shift 1 local STRING=${ARG} local LENGTH=$(expr length ${STRING}) local FIRSCHAR=$(echo $(expr substr ${STRING} 1 1)) local REST=$(echo $(expr substr ${STRING} 2 ${LENGTH})) \ps -eo 'user,pid,pcpu,command' w | grep "[${FIRSCHAR}]${REST}" done else \ps -eo 'user,pid,pcpu,command' w | grep -iE "(${*})" fi }


    -10
    psgrep() ... func to long, please look under "description"
    Xk2c · 2015-01-01 02:58:48 8
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Analyse writing style of writing style of a document
Style analyses the surface characteristics of the writing style of a document. It prints various readability grades, length of words, sentences and paragraphs. It can further locate sentences with certain characteristics. If no files are given, the document is read from standard input. style is part of "diction" package

interactive rss-based colorful commandline-fu reader perl oneliner (v0.1)
required packages: curl, xml2, html2text command is truncated, see 'sample output'

Record live sound in Vorbis (eg for bootlegs or to take audio notes)
This will record the capture channel of your soundcard, directly encoded in Ogg Vorbis, in stereo at quality 5 (I'm using this to record live jam sessions from my line input). You can choose which device to capture (eg. line input, microphone or PCM output) with $ alsamixer -V capture You can do the same thing and live encode in MP3 or FLAC if you wish, just check FLAC and LAME man pages.

This allows you to find a string on a set of files recursivly
The -r is for recursive, -F for fixed strings, --include='*.txt' identifies you want all txt files to be search any wildcard will apply, then the string you are looking for and the final * to ensure you go through all files and folders within the folder you execute it.

List all NPM global packages installed

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

Compare copies of a file with md5
I had the problem that the Md5 Sum of a file changed after copying it to my external disk. This unhandy command helped me to fix the problem.

Find files and list them sorted by modification time
Works with files containing spaces and for very large directories.

This command provides more color variety for the rainbow-like appearance by generating random color codes from 16 to 231 for adb logcat.

Are the two lines anagrams?
This is just a slight alternative that wraps all of #7917 in a function that can be executed


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