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…

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

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…

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.

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…

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…

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. …

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…

mohamad wael

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