this post was submitted on 11 Apr 2024
166 points (95.1% liked)

Linux

48220 readers
724 users here now

From Wikipedia, the free encyclopedia

Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

Rules

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago
MODERATORS
 

I'm curious how software can be created and evolve over time. I'm afraid that at some point, we'll realize there are issues with the software we're using that can only be remedied by massive changes or a complete rewrite.

Are there any instances of this happening? Where something is designed with a flaw that doesn't get realized until much later, necessitating scrapping the whole thing and starting from scratch?

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 1 points 7 months ago

But yeah I dunno in what cases rust is faster than C/C++.

First of all C and C++ are very different, C is faster than C++. Rust is not intrinsically faster than C in the same way that C is faster than C++, however there's a huge difference, safety.

Imagine the following C function:

void do_something(Person* person);

Are you sure that you can pass NULL? Or that it won't delete your object? Or delete later? Or anything, you need to know what the function does to be sure and/or perform lots of tests, e.g. the proper use of that function might be something like:

if( person ) {
  person_uses++;
  do_something(person);
}

...

if( --person_uses == 0 )
  free( person )

That's a lot more calls than just calling the function, but it's also a lot more secure.

In C++ this is somewhat solved by using smart pointers, e.g.

void do_something(std::unique_ptr<Person> person);
void something_else(std::shared_ptr<Person> person);

That's a lot more secure and readable, but also a lot slower. Rust achieves the C++ level of security and readability using only the equivalent of a single C call by performing pre-compile analysis and making the assembly both fast and secure.

Can the same thing be done on C? Absolutely, you could use macros instead of ifs and counters and have a very fast and safe code but not easy to read at all. The thing is Rust makes it easy to write fast and safe code, C is faster but safe C is slower, and since you always want safe code Rust ends up being faster for most applications.