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Replace underscores with spaces in filenames and dirnames, recursively into subdirs.
Everyone wants to take spaces out of filenames. Forget that. I want to put them back in. We've got tools and filesystems that support spaces, they look better, so I'm going to use them. Because of how find works I find I need to run this multiple times, if it's renaming subdirs. But it can be re-run without issues. I got this version of the command from a comment in this underscore-generating command. http://www.commandlinefu.com/commands/view/760/find-recursively-from-current-directory-down-files-and-directories-whose-names-contain-single-or-multiple-whitespaces-and-replace-each-such-occurrence-with-a-single-underscore. All I did was change the regex.

Block known dirty hosts from reaching your machine
Blacklisted is a compiled list of all known dirty hosts (botnets, spammers, bruteforcers, etc.) which is updated on an hourly basis. This command will get the list and create the rules for you, if you want them automatically blocked, append |sh to the end of the command line. It's a more practical solution to block all and allow in specifics however, there are many who don't or can't do this which is where this script will come in handy. For those using ipfw, a quick fix would be {print "add deny ip from "$1" to any}. Posted in the sample output are the top two entries. Be advised the blacklisted file itself filters out RFC1918 addresses (10.x.x.x, 172.16-31.x.x, 192.168.x.x) however, it is advisable you check/parse the list before you implement the rules

Kill XMMS for a cron job

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.

Show LAN IP with ip(8)
$ ip address show | grep eth0 | sed '1d' | awk '{print $2}' does the same, but shows network-prefix.

print shared library dependencies
May be used on (embedded) systems lack ldd

Take a screenshot of a login screen
when using Gnome or KDE, you will have a hard time getting a screenshot of something like a login screen, or any other screen that occurs before the desktop environment is up and monitoring the printscreen key. (this probably applies for other DEs as well, but I haven't used them) What this command is meant to do is take a screenshot of an X window using a command you can run from your virtual terminals (actual text terminals, not just an emulator) To do this: Press CTRL+ALT+F1 to go to a virtual (text) terminal once your login window comes up Login to the virtual terminal and enter the command (you'll have to type it in) You should now have a file called screenshot.png in your home directory with your screenshot in it. For those of you who are new to the virtual terminal thing, you can use CTRL+ALT+F7 to get back to your regular GUI From http://www.gnome.org

list block devices
Shows all block devices in a tree with descruptions of what they are.

Pulse Volume Control Using Zenity
This produces a little bar that you can use to set the volume percentage.


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