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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" }

Run the last command as root - (Open)Solaris version with RBAC

Parse m3u playlist file for total time
Parse an m3u file with seconds for each item and output the length of the entire playlist

debian/ubuntu get installed nvidia driver version from terminal
i've been writing a bash script where i needed to query the installed version number of the nvidia driver when it's not loaded. Unfortunately i have not found a easy way of doing this. If i'm a stupid person, please enlighten me of a better way ;)

Prints any IP out of a file

Encode file path to URL
Really helpfull when play with files having spaces an other bad name. Easy to store and access names and path in just a field while saving it in a file. This format (URL) is directly supported by nautilus and firefox (and other browsers)

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"

run command on a group of nodes in parallel
The pee command is in the moreutils package.

Create user add lines from partial passwd file
Handy if you are installing a new server or recovering an old one and you have a passwd file with the accounts you want to add to the server. If you edit the file so that only the accounts that you want to add are left this line will spit out the correct useradd lines. The uid, gecos and shell will be preserved.

Drop or block attackers IP with null routes
Someone might attack on your system. You can drop attacker IP using IPtables. However, you can use route command to null route unwanted traffic. A null route (also called as blackhole route) is a network route or kernel routing table entry that goes nowhere. Matching packets are dropped (ignored) rather than forwarded, acting as a kind of very limited firewall. The act of using null routes is often called blackhole filtering.


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