Commands by gnugr (2)

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Open a file at the specified line
You may also use +line:column syntax.

Run bash on top of a vi session (saved or not saved), run multiple commands, instead of one at a time with :!(bashcommand), type exit and [enter] to get back to where you left off in vi.
Helps when I'm editing a script and want to double check some commands without having to exit out of vi multiple times or having to use another terminal session.

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" }

Number of CPU's in a system
/proc/cpuinfo contains information about the CPU. Search for "processor" in the /proc/cpuinfo file wc -l, counts the number of lines.

Clean up after a poorly-formed tar file
These days, most software distributed in tar files will just contain a directory at the top level, but some tar files don't have this and can leave you with a mess of files in the current folder if you blindly execute $ tar zxvf something.tar.gz This command can help you clean up after such a mistake. However, note that this has the potential to do bad things if someone has been *really* nasty with filenames.

Check if your desired password is already available in haveibeenpwnd database. This command uses the API provided by HIBP

add files to existing growable DVD using growisofs
replace "directory name with files to add to DVD" with actual directory containing files you want to add to growable DVD

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"

LVM2 Reduce
Just the commands for the lvreduce I keep forgetting.

convert a mp4 video file to mp3 audio file (multiple files)

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