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This script compares the modification date of /var/lib/dpkg/info/${package}.list and all the files mentioned there.
It could be wrong on noatime partitions.
Here is non-oneliner:
#!/bin/sh
package=$1;
list=/var/lib/dpkg/info/${package}.list;
inst=$(stat "$list" -c %X);
cat $list |
(
while read file; do
if [ -f "$file" ]; then
acc=$(stat "$file" -c %X);
if [ $inst -lt $acc ]; then
echo used $file
exit 0
fi;
fi;
done
exit 1
)
wget --user=username --password="$password" http://example.org/
Instead of hiding commands entirely from history, I prefer to use "read" to put the password into a variable, and then use that variable in the commands instead of the password. Without the "-e" and "-s" it should work in any bourne-type shell, but the -s is what makes sure the password doesn't get echoed to the screen at all. (-e makes editing work a bit better)
find . -type f -iname '*.flac' # searches from the current folder recursively for .flac audio files
| # the output (a .flac audio files with relative path from ./ ) is piped to
while read FILE; do FILENAME="${FILE%.*}"; flac -cd "$FILE" | lame -b 192 - "${FILENAME}.mp3"; done
# for each line on the list:
# FILE gets the file with .flac extension and relative path
# FILENAME gets FILE without the .flac extension
# run flac for that FILE with output piped to lame conversion to mp3 using 192Kb bitrate
all files in the directory get moved, in doing so the new name of the file is the original name with out spaces (using translate command)
This is a command template for achiving the following:
* loop over files --> find -name "" | while read file; do ...; done
* output progress --> echo -n .
* execute some command on each file and save output for later usage --> output=$()
* if command failed, open subshell and echo newline --> || (echo;...;...;)
* echo output of command --> echo "$output"
Replace the echo command with whatever commands you want.
'read' reads a line from stdin and places the text in the variable, the stdin of the while loop comes from the find command.
Note that with simple commands, an easier way is using the '-exec' option of find. My command is useful if you want to execute multiple commands in the loop.
Thanks th John_W for suggesting the fix allowing ~/ to be used when saving a directory.
directions:
Type in a url, it will show a preview of what the file will look like when saved, then asks if you want to save the preview and where you want to save it. Great for grabbing the latest commandlinefu commands without a full web browser or even a GUI. Requires: w3m
The above is an example of grabbing only the first column. You can define the start and end points specifically by chacater position using the following command:
while read l; do echo ${l:10:40}; done < three-column-list.txt > column-c10-c40.txt
Of course, it doesn't have to be a column, or extraction, it can be replacement
while read l; do echo ${l/foo/bar}; done < list-with-foo.txt > list-with-bar.txt
Read more about parameter expansion here:
http://wiki.bash-hackers.org/syntax/pe
Think of this as an alternative to awk or sed for file operations
This will save your open windows to a file (~/.windows).
To start those applications:
cat ~/.windows | while read line; do $line &; done
Should work on any EWMH/NetWM compatible X Window Manager.
If you use DWM or another Window Manager not using EWMH or NetWM try this:
xwininfo -root -children | grep '^ ' | grep -v children | grep -v '<unknown>' | sed -n 's/^ *\(0x[0-9a-f]*\) .*/\1/p' | uniq | while read line; do xprop -id $line _NET_WM_PID | sed -n 's/.* = \([0-9]*\)$/\1/p'; done | uniq -u | grep -v '^$' | while read line; do ps -o cmd= $line; done > ~/.windows
Revised approach to and3k's version, using pipes and read rather than command substitution. This does not require fiddling with IFS when paths have whitespace, and does not risk hitting command-line size limits.
It's less verbose on the missing files, but it stops iterating at the first file that's missing, so it should be definitely faster.
I expanded all the qlist options to be more self-describing.
This shows every bit of information that stat can get for any file, dir, fifo, etc. It's great because it also shows the format and explains it for each format option.
If you just want stat help, create this handy alias 'stath' to display all format options with explanations.
alias stath="stat --h|sed '/Th/,/NO/!d;/%/!d'"
To display on 2 lines:
( F=/etc/screenrc N=c IFS=$'\n'; for L in $(sed 's/%Z./%Z\n/'<<<`stat --h|sed -n '/^ *%/s/^ *%\(.\).*$/\1:%\1/p'`); do G=$(echo "stat -$N '$L' \"$F\""); eval $G; N=fc;done; )
For a similarly powerful stat-like function optimized for pretty output (and can sort by any field), check out the "lll" function
From my .bash_profile ->
http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
This provides a way to sort output based on the length of the line, so that shorter lines appear before longer lines. It's an addon to the sort that I've wanted for years, sometimes it's very useful. Taken from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
Plays the mp3 stream of The Current as a background job. When you are done run:
fg %1
then to exit
Quite possible with Growl for mac I'd guess, although have not tried.
Libnotify needed for notification, stream will still work otherwise
Some servers don't have ssh-copy-id, this works in those cases.
It will ask for the destination server, this can be IP, hostname, or user@hostname if different from current user.
Ssh keygen will let you know if a pubkey already exists on your system and you can opt to not overwrite it.
in "a.html", find all images referred as relative URI in an HTML file by "src" attribute of "img" element, replace them with "data:" URI. This useful to create single HTML file holding all images in it, as a replacement of the IE-created .mht file format. The generated HTML works fine on every other browser except IE, as well as many HTML editors like kompozer, while the .mht format only works for IE, but not for every other browser. Compare to the KDE's own single-file-web-page format "war" format, which only opens correctly on KDE, the HTML file with "data:" URI is more universally supported.
The above command have many bugs. My commandline-fu is too limited to fix them:
1. it assume all URLs are relative URIs, thus works in this case:
<img src="images/logo.png"/>
but does not work in this case:
<img src="http://www.my_web_site.com/images/logo.png" />
This may not be a bug, as full URIs perhaps should be ignored in many use cases.
2. it only work for images whoes file name suffix is one of .jpg, .gif, .png, albeit images with .jpeg suffix and those without extension names at all are legal to HTML.
3. image file name is not allowed to contain "(" even though frequently used, as in "(copy of) my car.jpg". Besides, neither single nor double quotes are allowed.
4. There is infact a big flaw in this, file names are actually used as regular expression to be replaced with base64 encoded content. This cause the script to fail in many other cases. Example: 'D:\images\logo.png', where backward slash have different meaning in regular expression. I don't know how to fix this. I don't know any command that can do full text (no regular expression) replacement the way basic editors like gedit does.
5. The original a.html are not preserved, so a user should make a copy first in case things go wrong.
Create a text file called domainlist.txt with a domain per line, then run the command above. All registries are a little different, so play around with the command. Should produce a list of domains and their expirations date. I am responsible for my companies domains and have a dozen or so myself, so this is a quick check if I overlooked any.
If you have used bash for any scripting, you've used the date command alot. It's perfect for using as a way to create filename's dynamically within aliases,functions, and commands like below.. This is actually an update to my first alias, since a few commenters (below) had good observations on what was wrong with my first command.
# creating a date-based ssh-key for askapache.github.com
ssh-keygen -f ~/.ssh/`date +git-$USER@$HOSTNAME-%m-%d-%g` -C 'webmaster@askapache.com'
# /home/gpl/.ssh/git-gplnet@askapache.github.com-04-22-10
# create a tar+gzip backup of the current directory
tar -czf $(date +$HOME/.backups/%m-%d-%g-%R-`sed -u 's/\//#/g' <<< $PWD`.tgz) .
# tar -czf /home/gpl/.backups/04-22-10-01:13-#home#gpl#.rr#src.tgz .
I personally find myself having to reference
date --help
quite a bit as a result. So this nice alias saves me a lot of time. This is one bdash mofo. Works in sh and bash (posix), but will likely need to be changed for other shells due to the parameter substitution going on.. Just extend the sed command, I prefer sed to pretty much everything anyways.. but it's always preferable to put in the extra effort to go for as much builtin use as you can. Otherwise it's not a top one-liner, it's a lazyboy recliner.
Here's the old version:
alias dateh='date --help|sed "/^ *%%/,/^ *%Z/!d;s/ \+/ /g"|while read l;do date "+ %${l/% */}_${l/% */}_${l#* }";done|column -s_ -t'
This trick from my [ http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html bash_profile ]
cat mod_log_config.c | shmore
or
shmore < mod_log_config.c
Most pagers like less, more, most, and others require additional processes to be loaded, additional cpu time used, and if that wasn't bad enough, most of them modify the output in ways that can be undesirable.
What I wanted was a "more" pager that was basically the same as running:
cat file
Without modifying the output and without additional processes being created, cpu used, etc. Normally if you want to scroll the output of cat file without modifying the output I would have to scroll back my terminal or screen buffer because less modifies the output.
After looking over many examples ranging from builtin cat functions created for csh, zsh, ksh, sh, and bash from the 80's, 90s, and more recent examples shipped with bash 4, and after much trial and error, I finally came up with something that satisifed my objective. It automatically adjusts to the size of your terminal window by using the LINES variable (or 80 lines if that is empty) so
This is a great function that will work as long as your shell works, so it will work just find if you are booted in single user mode and your /usr/bin directory is missing (where less and other pagers can be). Using builtins like this is fantastic and is comparable to how busybox works, as long as your shell works this will work.
One caveat/note: I always have access to a color terminal, and I always setup both the termcap and the terminfo packages for color terminals (and/or ncurses and slang), so for that reason I stuck the
tput setab 4; tput setaf 7
command at the beginning of the function, so it only runs 1 time, and that causes the -- SHMore -- prompt to have a blue background and bright white text.
This is one of hundreds of functions I have in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html">.bash_profile at http://www.askapache.com/">AskApache.com, but actually won't be included till the next update.
If you can improve this in any way at all please let me know, I would be very grateful! ( Like one thing I want is to be able to continue to the next screen by pressing any key instead of now having to press enter to continue)
Taking file with ip ranges, each on it's own line like:
cat ipranges.txt
213.87.86.160-213.87.86.193
213.87.87.0-213.87.88.255
91.135.210.0-91.135.210.255
command returns deaggregated ip ranges using ipcalc deaggregate feature like that:
213.87.86.160/27
213.87.86.192/31
213.87.87.0/24
213.87.88.0/24
91.135.210.0/24
Useful for configuring nginx geo module