Welcome to bashoneliners.com, a curated collection of practical and well-explained Bash one-liners, snippets, tips and tricks. We aim to make each published one-liner to be 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.
echo /etc/*_ver* /etc/*-rel*; cat /etc/*_ver* /etc/*-rel*
(cd /var/log && ls syslog* | sort -n -t. -k2 | while read file; do echo "===== $file ====="; zcat "$file" || cat "$file"; done)
sudo cat /proc/1/smaps | grep '^Pss:' | tr -s ' ' | cut -d' ' -f2 | paste -sd+
while [ 1 == 1 ]; do cat /proc/loadavg | awk '{printf "1 minute load: %.2f\n", $(NF-5)}' && cat /proc/loadavg |awk '{printf "5 minute load: %.2f\n", $(NF-3)}' && cat /proc/loadavg |awk '{printf "15 minute load: %.2f\n", $(NF-2)}'; sleep 3; date; done
for ITEM in $(cat values_to_search.txt); do (egrep $ITEM full_values_list.txt && echo $ITEM found) | grep "found" >> exit_FOUND.txt; done
tty >/dev/null || { urxvt -e /bin/sh -c "tty >/tmp/proc$$; while test x; do sleep 1; done" & while test ! -f /tmp/proc$$; do sleep .1; done; FN=$(cat /tmp/proc$$); rm /tmp/proc$$; exec >$FN 2>$FN <$FN; }
cat post-list.csv | split -l 30 - --filter='jq -R . | jq --slurp -c .' | xargs -d "\n" -I % sh -c 'curl -H "Content-Type: application/json" -X POST -d '"'"'{"type":1,"entries":%}'"'"' http://127.0.0.1:8080/purge-something && sleep 30'
tr -dc a-z1-4 </dev/urandom | tr 1-2 ' \n' | awk 'length==0 || length>50' | tr 3-4 ' ' | sed 's/^ *//' | cat -s | fmt
files=("yourcert.crt" "provider.ca.pem") && for i in ${files[@]} ; do $(cat $i >> yourcert.pem && echo "" >> yourcert.pem) ; done
awk 'NR % 10 == 1 {getline f2 < "file1"; print f2} 1' file2 | cat -n
for i in $(cat /var/log/vsftpd.log | grep $DATE_TIME | grep UPLOAD | grep OK); do ls /FTP/HOME/$i >> /dev/null 2> \&1; if \[ $? = 0 \]; then echo "$i" >> $FILES_OK_UPLOADS.log; else echo "$DATE ERROR: File $i not found" >> $FTP_FILES_NOTOK_$DATE_TIME.log; fi; done
cat -n /path/to/file | less
pdftk input.pdf cat 2-4 7 9-10 output output.pdf
A=$(FILE=/var/log/myfile.log; cat $FILE | perl -p -e 's/.*,([A-Z]+)[\:\+].*/$1/g' | sort -u | while read LINE; do grep "$LINE" $FILE | wc -l | perl -p -e 's/[^0-9]+//g'; echo -e "\t$LINE"; done;);echo "$A"|sort -nr
cat ipsum.txt | perl -ne 'print map("$_\n", m/\w+/g);' | tr A-Z a-z | sort | uniq | awk 'length($1) == 4 {print}'
cat /tmp/log.data |colrm 1 155|colrm 60 300