commandlinefu.com is the place to record those command-line gems that you return to again and again.
Delete that bloated snippets file you've been using and share your personal repository with the world. 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.
If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/
You can sign-in using OpenID credentials, or register a traditional username and password.
First-time OpenID users will be automatically assigned a username which can be changed after signing in.
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.
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:
* Find all file sizes and file names from the current directory down (replace "." with a target directory as needed).
* sort the file sizes in numeric order
* List only the duplicated file sizes
* drop the file sizes so there are simply a list of files (retain order)
* calculate md5sums on all of the files
* replace the first instance of two spaces (md5sum output) with a \0
* drop the unique md5sums so only duplicate files remain listed
* Use AWK to aggregate identical files on one line.
* Remove the blank line from the beginning (This was done more efficiently by putting another "IF" into the AWK command, but then the whole line exceeded the 255 char limit).
>>>> Each output line contains the md5sum and then all of the files that have that identical md5sum. All fields are \0 delimited. All records are \n delimited.
"find ./ ..." could be replaced with "find $PWD ..." to display absolute path instead of relative path.
When trying to find an error in a hosted project it's interesting to find out how the source is organized: Are there .inc files? Or .php files only? Or .xml files that probably contain translated texts?
Analyze an Apache access log for the time period with most activity and display the hit count, requesting IP and the timestamp. May help detect a brute force dos attack.
cut can handle files as well. No neet for a cat.
Same as the rest, but handle IPv6 short IPs. Also, sort in the order that you're probably looking for.
The first sort is necessary for ips in a list to be actually unique.
The wajig package is not installed by default.
Show's per IP of how many requests they did to the Apache webserver
Compares the md5 checksums of the contents of two directories, outputting the checksum and filename where any files differ. Shows only the file name, not the full path.
Compute the md5 checksums for the contents of two mirrored directories, then sort and diff the results. If everything matches, nothing is returned. Otherwise, any checksums which do not match, or which exist in one tree but not the other, are returned. As you might imagine, the output is useful only if no errors are found, because only the checksums, not filenames, are returned. I hope to address this, or that someone else will!
bit of a contrived example and playing to my OCD but nice for quick scripted output of listening ports which is sorted by port, ip address and protocol.
Goes through all files in the directory specified, uses `stat` to print out last modification time, then sorts numerically in reverse, then uses cut to remove the modified epoch timestamp and finally head to only output the last 10 modified files.
Note that on a Mac `stat` won't work like this, you'll need to use either:
find . -type f -print0 | xargs -0 stat -f '%m%t%Sm %12z %N' | sort -nr | cut -f2- | head
or alternatively do a `brew install coreutils` and then replace `stat` with `gstat` in the original command.
The other commands were good, but they included packages that were installed and then removed.
This command only shows packages that are currently installed, sorts smallest to largest, and formats the sizes to be human readable.
bash-3.2$ find /logs -ls -xdev | sort -nrk 7 | head -10
1761905 205380 -rwxrwxr-x 1 wsadmin logadmin 210095353 Jul 22 01:33 /logs/intlpymt/Trace.log
652689 187360 -rwxrwxr-x 1 wsadmin logadmin 191663182 Jul 21 23:00 /logs/websphere/wsfpp1lppwa1213omsecureServer/SystemOut_13.07.21_23.00.12.log
2380449 186536 -rwxrwxr-x 1 wsadmin logadmin 190819939 Jul 16 14:03 /logs/omset/traceIntl.log.201307161403.lppwa1213.gz
2119524 183888 -rwxrwxr-x 1 wsadmin logadmin 188110111 Jul 22 01:33 /logs/intlpymt/intlpymtria/Trace.log
652816 160332 -rwxrwxr-x 1 wsadmin logadmin 164011871 Aug 14 2012 /logs/websphere/wsfpp1lppwa1213omsecureServer/SystemOut.log_08142012.gzip
653312 128916 -rwxrwxr-x 1 wsadmin logadmin 131873943 Jul 18 10:49 /logs/websphere/heapdump.20130718.104150.27592.0006.phd.201307181406.lppwa1213.gz
653320 128916 -rwxrwxr-x 1 wsadmin logadmin 131873735 Jul 18 10:40 /logs/websphere/heapdump.20130718.104012.27592.0002.phd.201307181406.lppwa1213.gz
653309 128912 -rwxrwxr-x 1 wsadmin logadmin 131867602 Jul 18 10:46 /logs/websphere/heapdump.20130718.104008.27592.0001.phd.201307181405.lppwa1213.gz
653323 128872 -rwxrwxr-x 1 wsadmin logadmin 131828157 Jul 18 10:41 /logs/websphere/heapdump.20130718.104109.27592.0004.phd.201307181407.lppwa1213.gz
652783 120288 -rwxrwxr-x 1 wsadmin logadmin 123047750 Aug 13 2012 /logs/websphere/wsfpp1lppwa1213omsecureServer/SystemOut.log_0813.2012.gzip