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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




Commands using sort from sorted by
Terminal - Commands using sort - 630 results
find . -type f -print0 | xargs -r0 stat -c %Y\ %n | sort -rn | gawk '{sub(/.\//,"",$2); print $2}' > /tmp/playlist.m3u
2009-03-04 16:41:02
User: microft
Functions: find gawk sort stat xargs

I use this to generate a playlist with all the podcasts I listen to.

Ordered from most recent to older.

du | sort -n | tail -11 | head
2009-03-04 16:06:34
User: phage
Functions: du sort tail

The pipe to head removes the listing of . as the largest directory.

zgrep "Failed password" /var/log/auth.log* | awk '{print $9}' | sort | uniq -c | sort -nr | less
2009-03-03 13:45:56
User: dbart
Functions: awk sort uniq zgrep

This command checks for the number of times when someone has tried to login to your server and failed. If there are a lot, then that user is being targeted on your system and you might want to make sure that user either has remote logins disabled, or has a strong password, or both. If your output has an "invalid" line, it is a summary of all logins from users that don't exist on your system.

gunzip -c /var/log/auth.log.*.gz | cat - /var/log/auth.log /var/log/auth.log.0 | grep "Invalid user" | awk '{print $8;}' | sort | uniq -c | less
du -cs * .[^\.]* | sort -n
2009-03-02 18:43:48
User: cemsbr
Functions: du sort

Very useful when you need disk space. It calculates the disk usage of all files and dirs (descending them) located at the current directory (including hidden ones). Then sort puts them in order.

sort -nt . -k 1,1 -k 2,2 -k 3,3 -k 4,4
2009-02-26 20:22:57
User: sysadmn
Functions: sort

Sort a list of IPV4 addresses in numerical order. Great as a filter, or within vim using !}

sort -bdf
2009-02-26 19:55:41
User: sysadmn
Functions: sort

Often, when sorting you want the sort to ignore extraneous characters. The b, d, and f tell sort to ignore leading blanks, use 'dictionary order' (ignore punctuation), and ignore (fold) case. Add a "u" if you only want one copy of duplicate lines.

This is a great command to use within vim to sort lines of text, using !}sort -bdf

du --max-depth=1 | sort -r -n | awk '{split("k m g",v); s=1; while($1>1024){$1/=1024; s++} print int($1)" "v[s]"\t"$2}'
2009-02-24 11:03:08
User: hans
Functions: awk du sort

I use this on debian testing, works like the other sorted du variants, but i like small numbers and suffixes :)

find . -type d | perl -nle 'print s,/,/,g," $_"' | sort -n | tail
find . -type f -name "*.java" -print0 | xargs -0 -n 1 svn blame | sed -n 's/^[^a-z]*\([a-z]*\).*$/\1/p' | sort | uniq -c | sort -n
sed -e "s/| /\n/g" ~/.bash_history | cut -d ' ' -f 1 | sort | uniq -c | sort -nr | head
"some line input" | sort | uniq -c | sort -nr
sed 's/[ \t]*$//' < emails.txt | tr 'A-Z' 'a-z' | sort | uniq > emails_sorted.txt
du -b --max-depth 1 | sort -nr | perl -pe 's{([0-9]+)}{sprintf "%.1f%s", $1>=2**30? ($1/2**30, "G"): $1>=2**20? ($1/2**20, "M"): $1>=2**10? ($1/2**10, "K"): ($1, "")}e'
comm -1 -2 <(sort file1) <(sort file2)
cat foo.csv bar.csv | sort -t "," -k 2 | uniq
2009-02-19 20:23:03
User: rafeco
Functions: cat sort

The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

lsof | awk '{print $1}' | sort | uniq -c | sort -rn | head
sed -n -e '/postfix\/smtp\[.*status=sent/s/^.*to=<\([^>]*\).*$/\1/p' /var/log/mail.log | sort -u
netstat -alpn | grep :80 | awk '{print $4}' |awk -F: '{print $(NF-1)}' |sort | uniq -c | sort -n
last | grep -v "^$" | awk '{ print $1 }' | sort -nr | uniq -c
2009-02-18 16:38:59
User: hkyeakley
Functions: awk grep last sort uniq

This command takes the output of the 'last' command, removes empty lines, gets just the first field ($USERNAME), sort the $USERNAMES in reverse order and then gives a summary count of unique matches.

diff <(sort file1.txt) <(sort file2.txt)
2009-02-18 15:17:59
Functions: diff sort

Sees if two records differ in their entries, irrespective of order.

history | awk '{print $2}' | sort | uniq -c | sort -rn | head
egrep -o '\b[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\b' access.log | sort -u
find path/to/folder/ -type f -print0 | xargs -0 -n 1 md5sum | awk '{print $1}' | sort | md5sum | awk '{print $1}'
2009-02-16 19:39:37
User: mcover
Functions: awk find md5sum sort xargs

For quick validation of folder's file-contents (structure not taken into account) - I use it mostly to check if two folders' contents are the same.

netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n | tail
2009-02-16 15:48:27
User: TuxOtaku
Functions: awk cut netstat sort uniq

This command does a tally of concurrent active connections from single IPs and prints out those IPs that have the most active concurrent connections. VERY useful in determining the source of a DoS or DDoS attack.