Check These Out
Using this command you can track a moment when usb device was attached.
This will record the capture channel of your soundcard, directly encoded in Ogg Vorbis, in stereo at quality 5 (I'm using this to record live jam sessions from my line input). You can choose which device to capture (eg. line input, microphone or PCM output) with
$ alsamixer -V capture
You can do the same thing and live encode in MP3 or FLAC if you wish, just check FLAC and LAME man pages.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.
This is a good alternative to pdf2text for Ubuntu. To install it:
sudo apt-get install python-pdfminer
Obviously the example given is necessarily simple, but this command not only saves time on the command line (saves you using "cd -" or, worse, having to type a fully qualified path if your command cd's more than once), but is vital in scripts, where I've found the behaviour of "cd -" to be a little broken at times.
In bash, this turns on auto cd. If a command is just a directory name, it cd's into that directory.
The above is just a prove of concept based around the nested bash substitution. This could be useful in situations where you're in a directory with many filetypes but you only want to convert a few.
$ for f in *.bmp *.jpg *.tga; do convert $f ${f%.*}.png; done
or you can use ls | egrep to get more specific... but be warned, files with spaces will cause a ruckus with expansion but the bash for loop uses a space delimited list.
$ for f in $(ls | egrep "bmp$|jpg$|tga$"); do convert $f ${f%.*}.png; done
I'm guessing some people will still prefer doing it the sed way but I thought the concept of this one was pretty neat. It will help me remember bash substitutions a little better :-P
Joins each line that end with backslash (common way to mark line continuation in many languages) with the following one while removing the backslash.