Commands by asphaltleopard (2)

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

cd to (or operate on) a file across parallel directories
This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

Join the content of a bash array with commas
$ DOCKER_APP_VARS=(DATABASE_USER=dbuserro, DATABASE_PASSWORD=maipass) [jeff@omniscience container] (master)$ echo docker run $(printf -- " -e %s" ${DOCKER_APP_VARS[*]}) -name 12factorapp mattdm/fedora-small docker run -e DATABASE_USER=dbuserro, -e DATABASE_PASSWORD=maipass -name 12factorapp mattdm/fedora-small Note that the printf method by itsself doesn't include a newline (\n), so you'll need to embed it into an echo statement or something that does.

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

Encode a string using ROT47
This command will encode a string using the ROT47 cipher.

Disable the ping response
It really disables all ICMP responses not only the ping one. If you want to enable it you can use: $ sudo -s "echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all"

Like top, but for files

Show word-by-word differences between two latex files, in color

Recursively execute command on directories (.svn, permissions, etc)
The above command will set the GID bit on all directories named .svn in the current directory recursively. This makes the group ownership of all .svn folders be the group ownership for all files created in that folder, no matter the user. This is useful for me as the subversion working directory on my server is also the live website and needs to be auto committed to subversion every so often via cron as well as worked on by multiple users. Setting the GID bit on the .svn folders makes sure we don't have a mix of .svn metadata created by a slew of different users.

Move cursor to end of line

Hits per hour apache log


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: