bashoneliners.com

Welcome to bashoneliners.com, a growing collection of practical and well-explained Bash one-liners, snippets, tips and tricks. We review and improve every contributed one-liner to make sure it is of high quality: useful, easy to read, follows best practices, with clear, detailed, accurate explanation. These one-liners should help you automate tasks, troubleshoot problems, whether it be in system administration, file management, networking or programming.

0

Watch a mashup of many video files

L=5; while true; do; readarray -t paths < <(find . -type f -print | shuf -n 1); for i in "${!paths[@]}"; do; path=${paths[i]}; if ffprobe -i "$path" -show_entries format=duration -v quiet -of csv="p=0" > /dev/null; then; N=$(ffprobe -i "$path" -show_entries format=duration -v quiet -of csv="p=0"); D=${N%.*}; P=$((D / 100 * 25)); R=$((1 + RANDOM % D - P * 2)); S=$((P + RANDOM % R)); W=$((R / 4)); LEN=$((1 + RANDOM % L)); mpv "$path" --start="$S" --length="$LEN" --fs &> /dev/null; W=$(bc <<< "$LEN - 0.5"); sleep "$W"; unset 'paths[i]'; fi; done; done

July 6, 2023krypniok

2

Generate a sequence of numbers using Brace Expansion

for i in {1..10}; do echo "$i"; done

October 25, 2019diego

1

Scan all open local ports without any external programs

for i in {1..65535}; do (< "/dev/tcp/127.0.0.1/$i") &>/dev/null && { echo; echo "[+] Open Port at: $i"; }  || printf "."; done; echo

May 8, 2019Goeks1

0

Organise image by portrait and landscape

mkdir "portraits"; mkdir "landscapes"; for f in ./*.jpg; do WIDTH=$(identify -format "%w" "$f")> /dev/null; HEIGHT=$(identify -format "%h" "$f")> /dev/null; if [[ "$HEIGHT" > "$WIDTH" ]]; then mv "$f" portraits/ ; else mv "$f" landscapes/ ; fi; done

August 23, 2018Jab2870

0

Create a txt files with 10000 rows

for FILE in *.full ; do split -l 100000 $FILE; mv -f xaa `echo "$FILE" | cut -d'.' -f1`.txt; rm -f x*; done

August 22, 2018Kifli88

0

Up all docker services as detached mode over all immediate subdirectories

for dir in $(ls -d */); do eval $(cd $PWD/$dir && docker-compose up -d && cd ..); done;

August 17, 2018gatero

1

Take values from a list (file) and search them on another file

for ITEM in $(cat values_to_search.txt); do  (egrep $ITEM full_values_list.txt && echo $ITEM found) | grep "found" >> exit_FOUND.txt; done

May 16, 2018ManuViorel

1

Preserve your fingers from cd ..; cd ..; cd..; cd..;

up(){ DEEP=$1; for i in $(seq 1 ${DEEP:-"1"}); do cd ../; done; }

June 28, 2017alireza6677

1

Generate a sequence of numbers, one number per line

perl -e 'print "$_\n" for (1..10)'

May 30, 2017abhinickz6

1

Delete static and dynamic arp for /24 subnet

for i in {1..254}; do arp -d 192.168.0.$i; done

October 21, 2016dennyhalim.com

2

Convert all flac files in dir to mp3 320kbps using ffmpeg

for FILE in *.flac; do ffmpeg -i "$FILE" -b:a 320k "${FILE[@]/%flac/mp3}"; done;

September 20, 2015Orkan

1

Preserve your fingers from cd ..; cd ..; cd..; cd..;

upup(){ DEEP=$1; [ -z "${DEEP}" ] && { DEEP=1; }; for i in $(seq 1 ${DEEP}); do cd ../; done; }

June 9, 2015andreaganduglia

5

Nmap scan every interface that is assigned an IP

ifconfig -a | perl -lne 'print $_ for /\b(?!255)(?:\d{1,3}\.){3}(?!255)\d{1,3}\b/g' | xargs nmap -A -p0-

February 8, 2015ratchode

3

Generate a sequence of numbers using a simple for loop

for ((i=1; i<=10; ++i)); do echo $i; done

November 4, 2014bashoneliners

1

Extensive "cleanup" operations following "sudo yum upgrade"

sudo yum upgrade && for pkg in $(package-cleanup --orphans -q); do repoquery $(rpm -q $pkg --queryformat="%{NAME}") | grep -q ".*" && echo $pkg; done | xargs sudo yum -y remove && for pkg in $(package-cleanup --leaves --all -q); do repoquery --groupmember $pkg | grep -q "@" || echo $pkg; done

April 16, 2014openiduser143

1

Concatenate multiple SSL certificate files to make one PEM file

files=("yourcert.crt" "provider.ca.pem") && for i in ${files[@]} ; do $(cat $i >> yourcert.pem && echo "" >> yourcert.pem) ; done

April 2, 2014renoirb

0

Count the lines of each file extension in a list of files

git ls-files | xargs wc -l | awk -F ' +|\\.|/' '{ sumlines[$NF] += $2 } END { for (ext in sumlines) print ext, sumlines[ext] }'

November 9, 2013bashoneliners

1

Find which log files contain or don't contain a specific error message

for i in *.log; do grep OutOfMemo $i >/dev/null && echo $i oom || echo $i ok; done

September 13, 2013bashoneliners

6

Convert directory of videos to MP4 in parallel

for path in *.avi; do echo "${path%.avi}"; done | xargs -I{} -P9 HandBrakeCLI -i {}.avi -o {}.mp4

August 13, 2013shavenwarthog

0

Create fattal tone mapped images from a directory of raw images

for img in /path/to/rawimages/*.RW2; do pfsin ${img} | pfssize -x 1024 -y 768 | pfstmo_fattal02 -v -s 1 | pfsout /path/to/finished/${img%%}.jpg; done

June 3, 2013mmaki

0

Rename all files in a directory to upper case

for i in *; do mv "$i" "${i^^}"; done

April 20, 2013EvaggelosBalaskas

7

Rename all items in a directory to lowercase names

for name in *; do mv "$name" "${name,,}"; done

April 20, 2013EvaggelosBalaskas

0

How to expand a CIDR notation to its IPs

for j in $(seq 0 255); do for i in $(seq 0 255) ; do seq -f "10.$j.$i.%g" 0 255; done; done

January 16, 2013EvaggelosBalaskas

0

Rename files with numeric padding

perl -e 'for (@ARGV) { $o = $_; s/\d+/sprintf("%04d", $&)/e; print qq{mv "$o" "$_"\n}}'

October 6, 2012bashoneliners

0

Run command multiple times with a for loop and a sequence expression

for i in {1..10}; do date; sleep 1; done

August 19, 2012bashoneliners