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Find the dates your debian/ubuntu packages were installed.
Find when debian packages were installed on a system.

take a look to command before action
add |sh when you agree the list, I often use that method to prevent typos in dangerous or long operations

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"

Add all unversioned files to svn
No need for grep, let awk do the match. This will not behave properly if the filenames contains whitespace, which is awk's default field separator.

ARP Scan
A much quicker and (not dirtier) option. use the man page for help. On linux/ubuntu you will need to `sudo apt-get -y install arp-scan`.

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" }

Debug redirects between production reloads
Watches the headers of a curl, following any redirects and printing only the HTTP status and the location of the possible redirects.

Find the package that installed a command

Replace all tabs with spaces in an application
Note that this assumes the application is an SVN checkout and so we have to throw away all the .svn files before making the substitution.

Ext3 format Terabytes in Seconds


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