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Function to split a string into an array

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Find the package that installed a command

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" }

Download from Rapidshare Premium using wget - Part 1
In order to do that, first you need to save a cookie file with your account info. These commands do it (maybe you need to create the '.cookies' dir before). Also, you need to check the "Direct downloads" option on the Premium Zone >> Settings tab. You need to do this once (as long you maintain the file or your Rapidshare Premium account).

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"

Print Memory Utilization Percentage For a specific process and it's children
Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.

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.

Convert ascii string to hex
Here's a version that uses perl. If you'd like a trailing newline: $ perl -pe 's/(.)/sprintf("\\x%x", ord($1))/eg; END {print "\n"}'

Displays the current time using HTTP
This command will show the current GMT time using HTTP. This might be useful if you just want to know what's the current human-readable and accurate-enough time, without changing the system time, using a simple command that would work regardless of the availability of NTP. Note: To get a quicker and more accurate response, replace google.com with your local NTP server. Also can be used as an alternative to the "htpdate" program: http://www.commandlinefu.com/commands/view/668/set-your-computers-clock-using-http-and-htp-http-time-protocol-when-ntpsntp-is-not-available


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