All commands (14,187)

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.

Share Your Commands


Check These Out

Continuously show wifi signal strength on a mac
The closer to zero the better.Credit to TheSeb on macrumors: http://forums.macrumors.com/showthread.php?t=1289884

preprocess code to be posted in comments on this site
Assuming that $script contains the filename of a script you'd like to post as part of a comment on this site, this will prefix each line with '$' and pipe it into the X selection. From there just put the cursor in the right place in the comments box and middle-click. Should work pretty much anywhere with xclip installed. On debian-ish systems this is installed as part of the package "xclip".

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Delete Empty Directories
Deletes empty directories and prints an error if directory is not empty.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Labyrinth pattern
Generates labyrinth-like pattern on UTF-8 terminal in bash. For fun ;)

list block devices
Shows all block devices in a tree with descruptions of what they are.

Put uppercase letters in curly brackets in a BibTeX database
It is often recommended to enclose capital letters in a BibTeX file in braces, so the letters will not be transformed to lower case, when imported from LaTeX. This is an attempt to apply this rule to a BibTeX database file. DO NOT USE sed '...' input.bib > input.bib as it will empty the file! How it works: $ /^\s*[^@%]/ Apply the search-and-replace rule to lines that start (^) with zero or more white spaces (\s*), followed by any character ([...]) that is *NOT* a "@" or a "%" (^@%). $ s===g Search (s) for some stuff and replace by other stuff. Do that globally (g) for all matches in each processed line. $ \([A-Z][A-Z]*\)\([^}A-Z]\|},$\) Matches at least one uppercase letter ([A-Z][A-Z]*) followed by a character that is EITHER not "}" and not a capital letter ([^}A-Z]) OR (|) it actually IS a "}", which is followed by "," at the end of the line ($). Putting regular expressions in escaped parentheses (\( and \), respectively) allows to dereference the matched string later. $ {\1}\2 Replace the matched string by "{", followed by part 1 of the matched string (\1), followed by "}", followed by the second part of the matched string (\2). I tried this with GNU sed, only, version 4.2.1.

Download YouTube Videos using wget and youtube-dl and just using the video link
in place of "output-filename.mp4" put the name you want the file to be named with. in place of "youtube-video-link" put the link of the Video page eg: http://www.youtube.com/watch?v=AclA-7YntvE in place of "format-number" put the number of the file format you would like How to get the "format-number" to get format number type in below command before running this command $ youtube-dl -F "youtube-video-link" and it will list all the available formats with the format number, like to download in 360p mp4 use the number "18" To automatically let it fetch the best quality available just remove the -f "format-number" and you are good to go.

speedtest
alias speedtest='wget --output-document=/dev/null http://speedtest.wdc01.softlayer.com/downloads/test500.zip'


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: