— So is he like a superman?

— Yeh, but he is tacit about it, you will never know about his existence.

— He is our hero! he is our hero! he is our hero!

— What is this, is this his birthday?

— Oh it is like everyday is his birthday, you can never stop hearing about his deeds, save this, save that, people cheering for him, hey, hey, we need you man!

— Yeh but come on, he is tacit about it!

— The humanitarian?

— Yeh, for certain, his popularity is on the rise.

— He does…


Ruby was created in 1995, which is about twenty-six years ago, by Yukihiro Matsumoto.

His aim when designing the language, was to create a scripting language, so scripting as in open this, read that, close this, so scripting as in a language, which is more human readable, and simpler to use than a non scripting language, for example C or java


While trying to use certbot, and if you face the error:

pkg_resources.DistributionNotFound: The 'chardet' distribution was not found and is required by acme

This means that you need to install chardet, which can be done by issuing:

sudo pip3 install chardet

If you are using macOS, make sure that pip3 is the one of python3.9, so if you are using macports issue:

sudo port install py39-pip
sudo port select --set pip3 pip39

Everything in python is an object. An object has a type, which defines its attributes and methods. For example the str type, define the attributes and methods for a string object. An object has also an id, which is its memory address, and it has a value, for example 1 or a

To compare objects in python, we can implement python comparison methods __eq__ , __ne__ , __lt__ , __gt__ , __ge__ , __le__. In this article we will show how to implement these methods, and how they work.

The comparison methods

introduction

All types in python, extends the object type. As such when…


The man command, is used to display a man page . It takes the name of the manual page to display, which is usually the same as the name of a command, or a function, or a special device… By default man is case insensitive.

debian:~$ man 
# When no manual page is supplied
# to man, it will display a similar
# message:
What manual page do you want?
debian:~$ man echo
# Display the echo command,
# manual page, which is located
# in:
# /usr/share/man/man1/echo.1.gz
debian:$ man -l /usr/share/man/man1/echo.1.gz
# The -l option specify the
# location of…

By default, the apropos command, searches the mandb database, keys and values, in a case insensitive way, using regular expressions.

bind -> "- 2 2 1557252946 0 A - - gz bind a name to a socket"
..
# The database, that apropos searches
# in, contains keys and values.
# key -> value
# item name -> description
# key is the name of a user
# command, or of a system or a
# library call...
# value, is the description,
# of this user command, or of
# this system, or library call.
# value additionally contains,
# the manual section, to…

whatis is used to search in a case insensitive way, the mandb database, for the name of a command, a library function, or a system call… in order to display its description.

whatis only searches the database keys, and not the description associated with these keys.

bind -> "- 2 2 1557252946 0 A - - gz bind a name to a socket"
..
# The database, that whatis searches
# in, contains keys and values.
# key -> value
# item name -> description
# key is the name of a user
# command, or of a system or a
#…

Historically, when unix was brought into life, and in order to explain its capabilities and features, a user manual was created.

This manual was divided into sections, each of which explained a specific topic, such as user commands, function calls, system calls, by providing individual pages, the man pages, which explain for example, a user command, a function, a device file, and the like.

debian:/usr/share/man$ ls
cs es fr.ISO8859-1 hu ja man2 man5 man8 pt sl tr
da fi fr.UTF-8 id ko man3 man6 nl pt_BR sr zh_CN
de fr hr it man1 man4 man7 pl ru sv zh_TW
# Electronically, the manual is…

What is the sizeof operator?

The sizeof operator, returns the size of an expression, or of an object type in C. An expression is for example 1 + 2, an object is any region of memory, and a type is for example int. The value returned by the sizeof operator, is of type size_t, and its unit is byte.

sizeof( Type )
/* When using sizeof with an object type
such as an int, the parenthesis ()
must be used .*/

sizeof expression
sizeof( expression )
/* When the sizeof operator is used
with an expression, the parenthesis ()
can or cannot be used .*/


An arm processor, can switch and operate on multiple instruction sets. Some of the instruction sets, that an arm processor can operate on, are thumb, which is a 16 bit instruction set, thumb2 which combines 16 and 32 bit instructions, aarch32 also known as arm32 or arm , and is a 32 bit instruction set, and finally arm64, also known as aarch64, which is also a 32 bit instruction set, but for 64 bit arm processors.

This tutorial will discuss, the arm32 instruction set.

Arm instruction format

Example

Some examples of arm instructions are:

add r0, r1, r2 
# Performs r1 + r2, and…

mohamad wael

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