Commands by cellularmitosis (1)

What's this? 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

Display all shell functions set in the current shell environment
Uses the shell builtin `declare` with the '-f' flag to output only functions to grep out only the function names. You can use it as an alias or function like so: alias shfunctions="builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'" shfunctions () { builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'; }

Detect if we are running on a VMware virtual machine
If you run this command on a VMWare Virtual Machine, it will return the string "VMware Virtual Platform". If you run it on a physical machine, it will return nothing. Useful for having a script determine if it's running on a VM or not. Of course, you must have dmidecode installed for this to work. Try it this way in a script: ISVM=$(dmidecode | awk '/VMware Virtual Platform/ {print $3,$4,$5}') Then test if $ISVM has text in it, or is blank.

write by vim need root privilege

Sending a file over icmp with hping
you need to start a listening hping on the reciever: hping3 --listen -I eth0 --sign MSGID1 then you can send your file: hping3 --icmp --sign MSGID1 -d 50 -c 1 --file a_file

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

Read aloud a text file in Mac OS X

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Rsync files with spaces
Using the double dash before the source and target makes the command work fine with weird filenames.

set desktop background to highest-rated image from Reddit /r/wallpapers
You'll need "feh" to set the background from the commandline. Install with "apt-get install feh" Thanks to the Redditors on this thread:

Google voice recognition "API"
The FLAC audio must be encoded at 16000Hz sampling rate (SoX is your friend). Outputs a short JSON string, the actual speech is in the hypotheses->utterance, the accuracy is stored in hypotheses->confidence (ranging from 0 to 1). Google also accepts audio in some special speex format (audio/x-speex-with-header-byte), which is much smaller in comparison with losless FLAC, but I haven't been able to encode such a sample.

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.


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: