Hacker News Reader

Comment by _delirium | Hacker News Reader

I would say most languages do. C is another one: the original AT&T C library has found its way via changes into some of the BSDs, but Linux systems typically use the GNU C library ("glibc"), which for copyright reasons had to be done as an independent implementation (the Unix source at the time was proprietary). Microsoft and IBM also have their own C library implementations.

View on HN

Apple, Intel, HP, ... also have their own C library implementations, to say nothing of dinkumware and musl-libc and ..., or the various glibc derivatives like eglibc and bionic. I could go on for quite a while, now that I think about it.

Bionic is a glibc derivative?

It is not, it contains pieces of various BSD libc derivatives:

http://codingrelic.geekhold.com/2008/11/six-million-dollar-l...

No, it’s not. Thanks for catching that (too late to edit, unfortunately).

(e)glibc and friends are fairly critical since they are the one exposing kernel features. Those that save a bit of space on embedded systems also have a selling point. For C++, aside from must-haves like open-source licences and community support, I don't see what the differentiators are.

> (e)glibc and friends are fairly critical since they are the one exposing kernel features.

By default. Unlike in Windows (from what I understand), in Unix-like OSes (Linux, the BSDs, probably others) it's entirely possible for user programs to talk directly to the kernel via a published API.

In Linux, C programs can use the syscall(2) function and x86 and x86-64 assembly language programs can use either the sysenter opcode or the int 0x80 interface, which is why linux-gate.so.1 exists and is mapped into every process: The kernel determines which method at boot and so userspace code (inclusive of libc) can't know in advance, so it uses the linux-gate.so.1 interface, instead.

http://www.trilithium.com/johan/2005/08/linux-gate/

http://articles.manugarg.com/systemcallinlinux2_6.html

http://stackoverflow.com/questions/9506353/how-to-invoke-a-s...

Reply on news.ycombinator.com