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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" }

Quick and dirty convert to flash
This converts any media ffmpeg handles to flash. It would actually convert anything to anything, it's based on the file extension. It doesn't do ANY quality control, sizing, etc, it just does what it thinks is best. I needed an flv for testing, and this spits one out easily.

get partitions that are over 50% usage

Jump to a directory, execute a command and jump back to current dir

Show all programs on UDP and TCP ports with timer information
-p PID and name of the program -u on a UDP port. -t also TCP ports -o networking timer -n numeric IP addresses (don't resolve them) -a all sockets

Create a continuous digital clock in Linux terminal
Same effect, only shell commands.

Quickly ping range of IP adresses and return only those that are online
Tested in Debian, ymmv. - c 1 : send only one ping;; -W 1: wait for one second and then exit ping, assuming target IP is not available; change as needed (-W 0.5 for half a second, smaller or greater value depending on network speed/latency)

Access partitions inside a LVM volume
kpartx can be found inside of the multipath-tools package -a adds the mappings and -d deletes them

Remove color codes (special characters) with sed

Create an SSH connection (reverse tunnel) through your firewall.
Allows you to establish a tunnel (encapsulate packets) to your (Server B) remote server IP from your local host (Server A). On Server B you can then connect to port 2001 which will forward all packets (encapsulated) to port 22 on Server A. -- www.fir3net.com --


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