Commands by powerinside (1)

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dd with progress bar and statistics
This command utilizes 'pv' to show dd's progress. Notes on use with dd: -- dd block size (bs=...) is a widely debated command-line switch and should usually be between 1024 and 4096. You won't see much performance improvements beyond 4096, but regardless of the block size, dd will transfer every bit of data. -- pv's switch, '-s' should be as close to the size of the data source as possible. -- dd's out file, 'of=...' can be anything as the data within that file are the same regardless of the filename / extension.

Quick HTML image gallery
My take on the original: even though I like the other's use of -exec echo, sed just feels more natural. This should also be slightly easier to improve. I expanded this into a script as an exercise, which took about 35 minutes (had to look up some docs): http://bitbucket.org/kniht/nonsense/src/7c1b46488dfc/commandlinefu/quick_image_gallery.py

Run a command as root, with a delay
$ sleep 1h ; sudo command or $ sudo sleep 1h ; sudo command won't work, because by the time the delay is up, sudo will want your password again.

Notepad in a browser
A commandline version of the notepad in a browser: http://www.commandlinefu.com/commands/view/12161/notepad-in-a-browser-type-this-in-the-url-bar All credit to the origional author of this fantastic command, whos only failing as most of the comments pointed out was that it wasn't a command... well, now its a command. Send all upvotes to dtlp747.

Show a line when a "column" matchs

count of down available ips

Query Wikipedia via console over DNS

Remove a line from a file using sed (useful for updating known SSH server keys when they change)
For example, to remove line 5 from foo, type: vi +5d +wq foo

Force machine to reboot no matter what (even if /sbin/shutdown is hanging)
This will cause your machine to INSTANTLY reboot. No un-mounting of drives or anything. Very handy when something has gone horribly wrong with your server in that co-location facility miles away with no remote hands! Suspect this works with all 2.2, 2.4 and 2.6 Linux kernels compiled with magic-syskey-request support.

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" }

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