Commands by matya (1)

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Start a command on only one CPU core
This is useful if you have a program which doesn't work well with multicore CPUs. With taskset you can set its CPU affinity to run on only one core.

Install pip with Proxy
Installs pip packages defining a proxy

Get a process's pid by supplying its name

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

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" }

Single use vnc-over-ssh connection
This command 1. SSH into a machine 2. Tunnels VNC port to your local computer ("-L 5900:localhost:5900") 3. Runs a single use vnc server ("x11vnc -safer -localhost -nopw -once -display :0") 4. Goes into the background ("-f") 5. Runs VNC viewer on the local computer connecting to the remote machine via the newly created SSH tunnel ("vinagre localhost:5900")

Redirect a filehandle from a currently running process.
This command uses the debugger to attach to a running process, and reassign a filehandle to a file. The two commands executed in gdb are p close(1) which closes STDOUT and p creat("/tmp/filename",0600) which creates a file and opens it for output. Since file handles are assigned sequentially, this command opens the file in place of STDOUT and once the process continues, new output to STDOUT will instead be written to our capture file.

Instant mirror from your laptop + webcam (fullscreen+grab)
This directly puts the "mirror" into fullscreen, and lets you take photos by pressing the 's' key. I bet appearance conscious people will have keyboard shortcut for this command by now.

list human readable files
include in the list human readable hidden files too: $ file .* *|grep 'ASCII text'|sort -rk2 more reliable command: $ ls|xargs file|grep 'ASCII text'|sort -rk2 and include hidden files: $ ls -a|xargs file|grep 'ASCII text'|sort -rk2

Generat a Random MAC address
Generate a random MAC address with capital letters

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