Commands by xrm0 (2)

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

delete duplicate lines from a file and keep the order of the other lines
i wanted to delete all duplicate lines from .bash_history and keep the order of the other lines. the command cat's the file and adds line numbers, then sorts by the second column. afterwards uniq omits repeated lines, but skips the first field (the line number). then it sorts by the line numbers and at the end cuts the numbers off.

Use all the cores or CPUs when compiling
Force make command to create as many compile processes as specified (4 in the example), so that each one goes into one core or CPU and compilation happens in parallel. This reduces the time required to compile a program by up to a half in the case of CPUs with 2 cores, one fourth in the case of quad cores... and so on.

aplay some whitenoise
Plays whitenoise from /dev/urandom.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

List the size (in human readable form) of all sub folders from the current location
Tested on MacOS and GNU/Linux. It works in dirs containing files starting with '-'. It runs 'du' only once. It sorts according to size. It treats 1K=1000 (and not 1024)

Print Memory Utilization Percentage For a specific process and it's children
Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.

Enable verbose boot in Mac OS X Open Firmware

Synchronize date and time with a server over ssh
Set Remote Server Date using Local Server Time (push)

Install a Firefox add-on/theme to all users
To install a theme use: $ sudo firefox -install-global-theme /path/to/theme You can get the .xpi or .jar file from the versions history on the add-on/theme page. NOTE: may not work in your system (Debian-based is an example).


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