Commands by silas (0)

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Record MP3 audio via ALSA using ffmpeg
Record audio to an MP3 file via ALSA. Adjust -i argument according to arecord -l output.

Create a file of a given size in linux
If you're trying to create a sparse file, you can use dd by 'skip'ing to the last block instance. ls -ls shows the actual size vs. the reported size

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Record live sound in Vorbis (eg for bootlegs or to take audio notes)
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.

Stamp a text line on top of the pdf pages.
To quickly add some remark, comment, stamp text, ... on top of (each of) the pages of the input pdf file.

Get your bash scripts to handle options (-h, --help etc) and spit out auto-formatted help or man page when asked!!
This will make your bash scripts better!! process-getopt is a wrapper around getopt(1) for bash that lets you define command line options (eg -h, --help) and descriptions through a single function call. These definitions are then used in runtime processing of command line options as well as in generating help and man pages. It also saves a little time in coding and in producing nicely formatted documentation. It is quite similar to GNU's argp in glibc for compiled languages and OptionParse for python. See: Linux Gazette article 162: http://tldp.org/LDP/LGNET/162/hepple.html, http://sourceforge.net/projects/process-getopt, http://bhepple.freeshell.org/oddmuse/wiki.cgi/process-getopt

Fetch the current human population of Earth
They are using json now

Get video information with ffmpeg
ffprobe is specially intended to get video information

a function to create a box of '=' characters around a given string.
The function 'box' takes either one or two arguments. The first argument is a line of text to be boxed, the second argument (optional) is a character to use to draw the box. By default, the drawing character will be '='. The function 'n()' is a helper function used to draw the upper and lower lines of the box, its arguments are a length, and an character to print. (I used 'n' because 'line', 'ln' and 'l' are all commonly used)

list block devices
Shows all block devices in a tree with descruptions of what they are.

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