Commands by Kaurin (1)

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MP3 player
I tried a few curses based mp3 players for playing back choir practice songs for my wife. Unfortunately none of the ones I tried were capable of scrubbing a track. Firefox saves the day.

Find the package that installed a command

List only directory names
This command would be useful when it is desirable to list only the directories. Other options Hidden directory $ ls -d .*/ Other path $ ls -d /path/to/top/directory/.*/ Long format: $ ls -ld */

Monitor logs in Linux using Tail
Works in Ubuntu, I hope it will work on all Linux machines. For Unixes, tail should be capable of handling more than one file with '-f' option. This command line simply take log files which are text files, and not ending with a number, and it will continuously monitor those files. Putting one alias in .profile will be more useful.

Start a HTTP server which serves Python docs
I use this command to start a local Python document server over HTTP port 8888.

Remove all unused kernels with apt-get
Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel). I'm bummed that this took 228 characters. I'd like to see a simpler version.

Synchronize date and time with a server over ssh
If you are stuck behind a firewall and want to synchronize time with another server but you do not want to port forward NTP (which uses UDP) then this command is handy. It gets the time from a server and sets the local time. It is not that accurate but I can live with a second or so drift.

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

Get line number of all matches in a file

Unite pdf files
pdfunite is a part of the poppler-utils. poppler-utils package is only 150KB. The alternative - pdftk package is 14MB! Install poppler-utils if you need simple pdf operation commands like unite, separate, info, text/html conversions

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