Page 8 – BEAUTY AND PLAY

Valavil RESEARCH: BLOG

perf: Linux profiling with performance counters

https://perf.wiki.kernel.org/index.php/Tutorial#Attaching_to_a_running_process

May 18, 2018
A bit field is a data structure used in computer programming

https://en.wikipedia.org/wiki/Bit_field

May 14, 2018
Search for a pattern at the beginning of a line using grep

$ps -e “kworker$” error: unknown sort specifier Usage: ps [options] Try ‘ps –help ‘ or ‘ps –help ‘ for additional help text. For more details see ps(1). $ps -ef | grep “^daemon” daemon 639 1 0 May04 ? 00:00:00 /usr/sbin/atd -f $ps -ef | grep “^rtkit” rtkit 1245 1 0 May04 ? 00:00:00 /usr/lib/rtkit/rtkit-daemon $ps […]

May 4, 2018
why does “exit status 0” mean success?

https://www.quora.com/in/Why-does-%E2%80%9Cexit-status-0%E2%80%9D-mean-success

April 7, 2018
Tinkering with trap and exit commands

TYPICAL COMMANDLINE SESSION [bash] $echo $? 0 $echo $? 0 $exit 10 | tee solve.txt $cat solve.txt $rm solve.txt $exit 10 | echo $? 0 $exit -1 | echo $? 0 $exit -1 | echo $? 0 $false | true $echo $? 0 $false $echo $? 1 $true $echo $? 0 $exit 5 | tee […]

April 7, 2018
Indicate how each name would be interpreted if used as a command name

$type -a locate locate is /usr/bin/locate $type -a ls ls is aliased to `ls –color=auto’ ls is /bin/ls $type -t ls alias $type -t locate file $type -t /dev/urandom $type -t /dev/sda1 $type -t urandom $type -t sda1 $type -t type builtin $type -t shuf file $type -t bash file $type -t proc $type -t […]

April 5, 2018
Non-deterministic Algorithms

https://cs.nyu.edu/courses/spring03/G22.2560-001/nondet.html

March 30, 2018
sort – sort lines of text files

$cat test.txt sept aug jan dec oct apr feb mar11 mar1 $sort test.txt apr aug dec feb jan mar1 mar11 oct sept $sort -M test.txt jan feb mar1 mar11 apr aug sept oct dec $

March 21, 2018
What is Tracker?

https://wiki.gnome.org/Projects/Tracker/WhatIsTracker

March 15, 2018
GNU Diffutils is a package of several programs related to finding differences between files

https://www.computerhope.com/unix/udiff.htm

March 15, 2018