Commands by weldabar (2)

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Extract audio stream from an AVI file using mencoder
This commands saves the output in the audio directory. The portion ${file/%avi/mp3} uses bash string replacement to replace the avi to mp3 within the ${file} variable.

Rename files in batch

Find the biggest files
Also: * find . -type f -exec ls -s {} \; | sort -n -r | head -5 * find . -type f -exec ls -l {} \; | awk '{print $5 "\t" $9}' | sort -n -r | head -5

View a sopcast stream
Get sopcast links for live sports from http://myp2p.eu (for example) Get sp-sc or sp-auth binary by googling (sopcast + linux) eg http://www.jbg.f2s.com/sp-sc.gz Requires the 32bit libstdc++5 package. After exiting mplayer, type 'killall sp-sc'

use jq to validate and pretty-print json output
the `jq` tool can also be used do validate json files and pretty print output `cat file.json | jq` available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/

wget progress bar with customized data size for dots

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

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Time conversion/format using the date command

Print a cron formatted time for 2 minutes in the future (for crontab testing)
Another function to stick into your .bashrc This spits out the time two minutes in the future, but already formatted for pasting into your crontab file for testing without any thought required on your part. Frequently things don't work the way you expect inside a crontab job, and you probably want to find out now that your $PATH is completely different inside of cron or other global variables aren't defined. So this will generate a date you can use for testing now, and then later you can change it to run at 5:37 am on a Sunday evening.


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