Commands by ifebi (1)

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Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

diff the same file in two directories.
This is useful when you're diffing two files of the same name in radically different directory trees. For example: Set $ path1='/some/long/convoluted/path/to/all/of/your/source/from/a/long/dead/machine' then $ path2='/local/version/of/same/file' then run the command. Much easier on the eyes when you're looking back across your command history, especially if you're doing the same diff over and over again.

Matrix - Just 1 wobbly line rather then a rain! (shorter)
No sample. Try it and see the magic!

Ride another SSH agent
Must be done as root - will cause subsequent ssh connections to use the identities available via the [user]'s agent socket.

Bash command to convert IP addresses into their "reverse" form

rsync + find
use find with rsync

Resume a partially copied file

Find Duplicate Files (based on MD5 hash) -- For Mac OS X
This works on Mac OS X using the `md5` command instead of `md5sum`, which works similarly, but has a different output format. Note that this only prints the name of the duplicates, not the original file. This is handy because you can add `| xargs rm` to the end of the command to delete all the duplicates while leaving the original.

Screencast of your PC Display with mp4 output
Since ffmpeg on Ubuntu is deprecated, now there is avconv. Please note that the screen area here is set with a predefined format "-s wxga" that is corresponding to "-s 1366x768") There is also the option to add a title in the metadata of the resulting video.

Replace Solaris vmstat numbers with human readable format
% cat ph-vmstat.awk # Return human readable numbers function hrnum(a) { b = a ; if (a > 1000000) { b = sprintf("%2.2fM", a/1000000) ; } else if (a > 1000) { b = sprintf("%2.2fK", a/1000) ; } return(b) ; } # Return human readable storage function hrstorage(a) { b = a ; if (a > 1024000) { b = sprintf("%2.2fG", a/1024/1024) ; } else if (a > 1024) { b = sprintf("%2.2fM", a/1024) ; } return(b) ; } OFS=" " ; $1 !~ /[0-9].*/ {print} $1 ~ /[0-9].*/ { $4 = hrstorage($4) ; $5 = hrstorage($5) ; $9 = hrnum($9) ; $10 = hrnum($10) ; $17 = hrnum($17) ; $18 = hrnum($18) ; $19 = hrnum($19) ; print ; }

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