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tree by modify time with newest file at bottom
Go look at sample output first This is kind of like the ls command but displays by modify time with size, date and color. The newest files at the bottom of the screen (reverse using tac)

Check if it's your binary birthday!
Print out your age in days in binary. Today's my binary birthday, I'm 2^14 days old :-) . This command does bash arithmatic $(( )) on two dates: Today: $(date +%s) Date of birth: $(date +%s -d YYYY-MM-DD) The dates are expressed as the number of seconds since the Unix epoch (Jan 1970), so we devide the difference by 86400 (seconds per day). . Finally we pipe "obase=2; DAYS-OLD" into bc to convert to binary. (obase == output base)

Find and display most recent files using find and perl
This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting. Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl? Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links.... Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process.

Install pip with Proxy
Installs pip packages defining a proxy

Compare an archive with filesystem
and you quickly know the files you changed

kill a process(e.g. conky) by its name, useful when debugging conky:)

rsync with progress bar.
transfer files from localhost to a remotehost.

View internet connection activity in a browser
In addition to generating the current connections, it also opens then in your default browser on gnome.

Unbelievable Shell Colors, Shading, Backgrounds, Effects for Non-X
I've been using linux for almost a decade and only recently discovered that most terminals like putty, xterm, xfree86, vt100, etc., support hundreds of shades of colors, backgrounds and text/terminal effects. This simply prints out a ton of them, the output is pretty amazing. If you use non-x terminals all the time like I do, it can really be helpful to know how to tweak colors and terminal capabilities. Like: $ echo $'\33[H\33[2J'

Create backup copy of file, adding suffix of the date of the file modification (NOT today's date)
When I go to change a configuration file I always like to make a backup first. You can use "cp -p" to preserve the modification time, but it gets confusing to have file.prev, file.prev2, etc. So I like to add a YYMMDD suffix that shows when the file was last changed. "stat -c %Y" gives you the modification time in epoch seconds, then "date -d @" converts that to whatever format you specify in your "+format" string.


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