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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.

Find the top 10 directories containing the highest number of files
It can be used to pinpoint the path(s) where the largest number of files resides when running out of free i-nodes

Check if you work on a virtual/physical machine in Linux
Command used to know if we are working on a virtual or physical machine. This command will use the dmidecode utility to retrieve hardware information of your computer via the BIOS. Run this command as root or with sudo.

lotto generator

Set up alarm with fade-in, for graceful awakening
There are a lot of commands, which invokes your player at specified time. But I prefer not to jump from by bed, when alarm start to play. Instead, this script increases volume of mpd over time, which much more pleasant when you just woke up :)

Live stream a remote desktop over ssh using only ffmpeg
Play with the framerate option '-r' to scale back bandwidth usage. The '-s' option is the captured screan area, not the rescaled size. If you want to rescale add a second '-s' option after '-i :0'. Rescaling smaller will also decrease bandwidth.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Function to output an ASCII character given its decimal equivalent
I've corrected the function. My octal conversion formula was completely wrong. Thanks to pgas at http://mywiki.wooledge.org/BashFAQ/071 for setting me straight. The new function is from pgas and is very fast.

HTML5 ogg player
find OGG audio files on your *nix box and listen to them using your web browser

Exclude inserting a table from a sql import
Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.


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