Commands tagged udp (6)

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Check if the LHC has destroyed the world
This says if the LHC has destroyed the world. Run it in a loop to monitor the state of Earth. Might not work reliable, if the world has actually been destroyed.

Adding specific CustomLog for each Virtual Domain of Apache

recursive search and replace old with new string, inside files
This command find all files in the current dir and subdirs, and replace all occurances of "oldstring" in every file with "newstring".

Detach a process from the current shell
Continue to execute the command in background even though quitting the shell.

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" }

Find the package that installed a command

Do one ping to a URL, I use this in a MRTG gauge graph to monitor connectivity

check open ports without netstat or lsof

Retrieve the size of a file on a server
Downloads the entire file, but http servers don't always provide the optional 'Content-Length:' header, and ftp/gopher/dict/etc servers don't provide a filesize header at all.

(Debian/Ubuntu) Discover what package a file belongs to
'dpkg -S' just matches the string you supply it, so just using 'ls' as an argument matches any file from any package that has 'ls' anywhere in the filename. So usually it's a good idea to use an absolute path. You can see in the second example that 12 thousand files that are known to dpkg match the bare string 'ls'.


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