Commands using head (314)
-
3awk '{print $1}' /var/log/httpd/access_log | sort | uniq -c | sort -rnk1 | head -n 10
-
3date +%s | sha256sum | base64 | head -c <length>; echo
-
Checks the apache configuration syntax, if is OK then restart the service otherwise opens the configuration file with VIM on the line where the configuration fails.
3( apache2ctl -t && service apache2 restart || (l=$(apache2ctl -t 2>&1|head -n1|sed 's/.*line\s\([0-9]*\).*/\1/'); vim +$l $(locate apache2.conf | head -n1))) -
perl-less way
3(netstat -atn | awk '{printf "%s\n%s\n", $4, $4}' | grep -oE '[0-9]*$'; seq 32768 61000) | sort -n | uniq -u | head -n 1 -
3du -hsx * | sort -rh | head -10
-
Short list about top 10 processes, sorted by CPU usage Show Sample Output
3ps aux | sort -rk 3,3 | head -n 10 -
3ps auxk -%cpu | head -n10
-
It displays the top 10 processes sorted by memory usage Show Sample Output
3ps aux | sort -rk 4,4 | head -n 10 -
2# cut -d ' ' -f1 /var/log/nginx/nginx-access.log | sort | uniq -c | sort -nr | head -10 | nl
-
Adjust the
head -cpart for password length. I use filenames like "hans@commandlinefu.com.gpg" and a vim which automatically decrypts files with .gpg suffixes.2tr -dc "a-zA-Z0-9-_\$\?" < /dev/urandom | head -c 10 | gpg -e -r medha@nerdish.de > password.gpg -
2ls -t1 | head -n1
-
Low on disk space? Check the largest installed RPMs for delete canditates. Show Sample Output
2rpm -qa --qf '%{SIZE} %{NAME}\n' | sort -nr | nl | head -6 # six largest RPMs -
Change ~/tmp to the destination directory, such as your mounted media. Change -n20 to whatever number of files to copy. It should quit when media is full. I use this to put my most recently downloaded podcasts onto my phone.
2find . -name \*.mp3 -printf "%C+ %h/%f\n" | sort -r | head -n20 | awk '{print "\""$2"\""}' | xargs -I {} cp {} ~/tmp -
2sort -R file.txt | head -1
-
2mysql -u<user> -p<password> -s -e 'DESCRIBE <table>' <database> | tail -n +1 | awk '{ printf($1",")}' | head -c -1
-
2find ~/Music -daystart -mtime -60 -name *mp3 -printf "%T@\t%p\n" | sort -f -r | head -n 30 | cut -f 2
-
2head -c4 /dev/urandom | od -N4 -tu4 | sed -ne '1s/.* //p'
-
2tr -c -d 0-9 < /dev/urandom | head -c 10
-
Same as original, but works in bash
2while [ 1 -lt 2 ]; do i=0; COL=$((RANDOM%$(tput cols)));ROW=$((RANDOM%$(tput cols)));while [ $i -lt $COL ]; do tput cup $i $ROW;echo -e "\033[1;34m" $(cat /dev/urandom | head -1 | cut -c1-1) 2>/dev/null ; i=$(expr $i + 1); done; done -
Just increase the 1 at the end if you want to generate more than one. (Alternative to "| head -n N" you could use the -b flag of od: -b $[6*N] Show Sample Output
2od /dev/urandom -w6 -tx1 -An|sed -e 's/ //' -e 's/ /:/g'|head -n 1 -
2alias cd1='cd $( ls -lt | grep ^d | head -1 | cut -b 51- )'
-
Specify the size in bytes using the 'c' option for the -size flag. The + sign reads as "bigger than". Then execute du on the list; sort in reverse mode and show the first 10 occurrences. Show Sample Output
2find /myfs -size +209715200c -exec du -m {} \; |sort -nr |head -10 -
combination of several of the above
2export GREP_COLOR='1;32';while [ true ]; do head -n 100 /dev/urandom; sleep .1; done | hexdump -C | grep --color=auto "ca fe" -
list the top 15 folders by decreasing size in MB Show Sample Output
2du -xB M --max-depth=2 /var | sort -rn | head -n 15 -
Feel free to put this in your ~/.profile:
random(){ cat /dev/urandom | env LC_CTYPE=C tr -dc $1 | head -c $2; echo; }Then use it to generate passwords:random [:alnum:] 16Or DNA sequences:random ACGT 2562cat /dev/urandom | env LC_CTYPE=C tr -dc a-zA-Z0-9 | head -c 16; echo - < 1 2 3 4 5 > Last ›
What's this?
commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.
Check These Out
Stay in the loop…
- Follow the Tweets.
-
Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.
» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10 - Subscribe to the feeds.
-
Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):
Subscribe to the feed for:
- » all commands
- » commands with 3 up-votes (commandlinefu3)
- » commands with 10 up-votes (commandlinefu10)
- » commands using head