Commands by thebillywayne (9)

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Connect to FreeWifi hotspot (France) and keep the connection active
(In French) Connection aux hotspots FreeWifi, et maintien de la connection active

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" }

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Remove all HTML tags from a file

Number of CPU's in a system
This appears to do the same. Utility is verified to be present on Ubuntu and OpenSuse out-of-the-box.

If (and only if) the variable is not set, prompt users and give them a default option already filled in.
The read command reads input and puts it into a variable. With -i you set an initial value. In this case I used a known environment variable.

Display the definition of a shell function
Display the code of a previously defined shell function.

Put terminal into vi mode
For if you want to use vi key bindings in the terminal

Pass TAB as field separator to sort, join, cut, etc.
Use this BASH trick to create a variable containing the TAB character and pass it as the argument to sort, join, cut and other commands which don't understand the \t notation. $ sort -t $'\t' ... $ join -t $'\t' ... $ cut -d $'\t' ...

count match string lines from file(s)


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