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

Reclaim standard in from the tty for a script that is in a pipeline
This will grab the controlling tty regardless of what STDOUT and STDERR are doing.

sends your internal IP by email
This is useful if you have need to do port forwarding and your router doesn't assign static IPs, you can add it to a script in a cron job that checks if you IP as recently changed or with a trigger script. This was tested on Mac OSX.

Clear the terminal screen

Determine status of a RAID write-intent bitmap
Report information about a bitmap file.

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" }

List only the directories
to include hidden dirs use: $ tree -adL 1 (with ls, requires 'ls -ad */ .*/')

Remove \r (carriage return) in a file

List of reverse DNS records for a subnet
This command uses nmap to perform reverse DNS lookups on a subnet. It produces a list of IP addresses with the corresponding PTR record for a given subnet. You can enter the subnet in CDIR notation (i.e. /24 for a Class C)). You could add "--dns-servers x.x.x.x" after the "-sL" if you need the lookups to be performed on a specific DNS server. On some installations nmap needs sudo I believe. Also I hope awk is standard on most distros.

Synchronize date and time with a server over ssh
Set Remote Server Date using Local Server Time (push)


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