Commands by xeor (15)

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Using the urxvt terminal daemon
- for .xsession use - Advantages of running a urxvt daemon include faster creation time for terminal windows and a lot of saved memory. You can start new terminals as childs of urxvtd by typing urxvtc. Another advantage is, that background jobs are always owned by the urxvtd and will survive as long the daemon is running.

All what exists in dir B and not in dir A will be copied from dir B to new or existing dir C
Assumed dir A, B, C are subdirs of the current dir Exact syntax of the command is: rsync -v -r --size-only --compare-dest=/path_to_A/A/ /path_to_B/B/ /path_to_C/C/ (do not omit end-slashes, since that would copy only the names and not the contents of subdirs of dir B to dir C) You can replace --size-only with --checksum for more thorough file differences validation Useful switch: -n, --dry-run perform a trial run with no changes made

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"

copy timestamps of files from one location to another - useful when file contents are already synced but timestamps are wrong.
Sometimes when copying files from one place to another, the timestamps get lost. Maybe you forgot to add a flag to preserve timestamps in your copy command. You're sure the files are exactly the same in both locations, but the timestamps of the files in the new home are wrong and you need them to match the source. Using this command, you will get a shell script (/tmp/retime.sh) than you can move to the new location and just execute - it will change the timestamps on all the files and directories to their previous values. Make sure you're in the right directory when you launch it, otherwise all the touch commands will create new zero-length files with those names. Since find's output includes "." it will also change the timestamp of the current directory. Ideally rsync would be the way to handle this - since it only sends changes by default, there would be relatively little network traffic resulting. But rsync has to read the entire file contents on both sides to be sure no bytes have changed, potentially causing a huge amount of local disk I/O on each side. This could be a problem if your files are large. My approach avoids all the comparison I/O. I've seen comments that rsync with the "--size-only" and "--times" options should do this also, but it didn't seem to do what I wanted in my test. With my approach you can review/edit the output commands before running them, so you can tell exactly what will happen. The "tee" command both displays the output on the screen for your review, AND saves it to the file /tmp/retime.sh. Credit: got this idea from Stone's answer at http://serverfault.com/questions/344731/rsync-copying-over-timestamps-only?rq=1, and combined it into one line.

Count the words in any OpenOffice document (including Impress presentations)
OpenOffice, LibreOffice and OO Impress wordcount

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

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"

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

Scan for nearby Bluetooth devices.
Scans local area for visible Bluetooth devices. Use 'hcitool inq' to discover the type of device it is. And use -i hciX option to specify the local Bluetooth device to use.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.


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