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Linux Kernel Interface
The Linux kernel provides several interfaces to user-space applications that are used for different purposes and that have different properties by design. There are two types of application programming interface (API) in the Linux kernel that are not to be confused: the "kernel–user space" API and the "kernel internal" API. Linux API The Linux API is the kernel–user space API, which allows programs in user space to access system resources and services of the Linux kernel. It is composed out of the System Call Interface of the Linux kernel and the subroutines in the GNU C Library (glibc). The focus of the development of the Linux API has been to provide the ''usable features'' of the specifications defined in POSIX in a way which is reasonably compatible, robust and performant, and to provide additional useful features not defined in POSIX, just as the kernel–user space APIs of other systems implementing the POSIX API also provide additional features not d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linux Kernel Interfaces
The Linux kernel provides several interfaces to user-space applications that are used for different purposes and that have different properties by design. There are two types of application programming interface (API) in the Linux kernel that are not to be confused: the "kernel–user space" API and the "kernel internal" API. Linux API The Linux API is the kernel–user space API, which allows programs in user space to access system resources and services of the Linux kernel. It is composed out of the System Call Interface of the Linux kernel and the subroutines in the GNU C Library (glibc). The focus of the development of the Linux API has been to provide the ''usable features'' of the specifications defined in POSIX in a way which is reasonably compatible, robust and performant, and to provide additional useful features not defined in POSIX, just as the kernel–user space APIs of other systems implementing the POSIX API also provide additional features no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
System Calls
In computing, a system call (commonly abbreviated to syscall) is the programmatic way in which a computer program requests a service from the operating system on which it is executed. This may include hardware-related services (for example, accessing a hard disk drive or accessing the device's camera), creation and execution of new processes, and communication with integral kernel services such as process scheduling. System calls provide an essential interface between a process and the operating system. In most systems, system calls can only be made from userspace processes, while in some systems, OS/360 and successors for example, privileged system code also issues system calls. Privileges The architecture of most modern processors, with the exception of some embedded systems, involves a security model. For example, the ''rings'' model specifies multiple privilege levels under which software may be executed: a program is usually limited to its own address space so that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix-like
A Unix-like (sometimes referred to as UN*X or *nix) operating system is one that behaves in a manner similar to a Unix system, although not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Unix-like application is one that behaves like the corresponding Unix command or shell. Although there are general philosophies for Unix design, there is no technical standard defining the term, and opinions can differ about the degree to which a particular operating system or application is Unix-like. Some well-known examples of Unix-like operating systems include Linux and BSD. These systems are often used on servers, as well as on personal computers and other devices. Many popular applications, such as the Apache web server and the Bash shell, are also designed to be used on Unix-like systems. One of the key features of Unix-like systems is their ability to support multiple users and processes simultaneously. This allows users to run multipl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybris (software)
Hybris or libhybris is a compatibility layer for computers running Linux distributions based on the GNU C library or Musl, intended for using software written for Bionic-based Linux systems, which mainly includes Android libraries and device drivers. History Hybris was initially written by Carsten Munk, a Mer developer, who released it on GitHub on 5 August 2012 and publicly announced the project later that month. Munk has since been hired by Jolla as their Chief Research Engineer. Hybris has also been picked up by the Open webOS community for WebOS Ports, by Canonical for Ubuntu Touch and by the AsteroidOS project. In April 2013, Munk announced that Hybris has been extended to allow Wayland compositors to use graphic device drivers written for Android. Weston has had support for libhybris since version 1.3, which was released on 11 October 2013. Features Hybris loads "Android libraries, and overrides some symbols from bionic with glibc" calls, making it possible to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bionic (software)
Bionic is an implementation of the standard C library, developed by Google for its Android operating system. It differs from the GNU C Library (glibc) in being designed for devices with less memory and processor power than a typical Linux system. It is a combination of new code and code from FreeBSD, NetBSD, and OpenBSD released under a BSD license, rather than glibc, which uses the GNU Lesser General Public License. This difference was important in the early days of Android, when static linking was common, and is still helpful in introducing Android to software companies used to proprietary operating systems, who can be wary of the LGPL, and unclear about the differences between it and the full GNU General Public License (GPL). Bionic is a C library for use with the Linux kernel, and provides libc, libdl, and libm ( libpthread functionality is part of libc, not a separate library as on some other systems). This differs from the BSD C libraries that bionic shares code with, becau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dietlibc
dietlibc is a C standard library released under the GNU General Public License Version 2, and proprietary licenses are also available. It was developed with the help of about 100 volunteers by Felix von Leitner with the goal to compile and link programs to the smallest possible size. dietlibc was developed from scratch and thus only implements the most important and commonly used functions. It is mainly used in embedded devices. See also *C standard libraries The C standard library or libc is the standard library for the C programming language, as specified in the ISO C standard.ISO/IEC (2018). '' ISO/IEC 9899:2018(E): Programming Languages - C §7'' Starting from the original ANSI C standard, it was ... References Further reading * * External links * Comparison of C/POSIX standard library implementations for Linux C standard library Free computer libraries Free software programmed in C Interfaces of the Linux kernel Linux APIs Software using the GPL licens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Musl
musl is a C standard library intended for operating systems based on the Linux kernel, released under the MIT License. It was developed by Rich Felker with the goal to write a clean, efficient and standards-conformant libc implementation. Overview musl was designed from scratch to allow efficient static linking and to have realtime-quality robustness by avoiding race conditions, internal failures on resource exhaustion and various other bad worst-case behaviors present in existing implementations. The dynamic runtime is a single file with stable ABI allowing race-free updates and the static linking support allows an application to be deployed as a single portable binary without significant size overhead. It claims compatibility with the POSIX 2008 specification and the C11 standard. It also implements most of the widely used non-standard Linux, BSD, and glibc functions. There is partial ABI compatibility with the part of glibc required by Linux Standard Base. Version 1.2.0 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newlib
Newlib is a C standard library implementation intended for use on embedded systems. It is a conglomeration of several library parts, all under free software licenses that make them easily usable on embedded products. It was created by Cygnus Support as part of building the first GNU cross-development toolchains. It is now maintained by Red Hat developers Jeff Johnston and Corinna Vinschen, and is used in most commercial and non-commercial GCC ports for non-Linux embedded systems. System Calls The section System Calls of the Newlib documentation describes how it can be used with many operating systems. Its primary use is on embedded systems that lack any kind of operating system; in that case it calls a board support package that can do things like write a byte of output on a serial port, or read a sector from a disk or other memory device. Inclusion Newlib is included in commercial GCC distributions by Atollic, CodeSourcery, Code Red, KPIT, Red Hat and others, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Klibc
In computing, klibc is a minimalistic subset of the standard C library developed by H. Peter Anvin. It was developed mainly to be used during the Linux startup process, and it is part of the early user space, i.e. components used during kernel startup, but which do not run in kernel mode.https://www.kernel.org/doc/Documentation/early-userspace/README These components do not have access to the standard library (usually glibc or musl) used by normal userspace programs. The development of klibc library was part of the 2002 effort to move some Linux initialization code out of the kernel. According to its documentation, the klibc library is optimized for correctness and small size. Because of its design, klibc is also technically suitable for embedded software in general on a variety of platforms, and is used even by full-featured programs such as the MirBSD Korn Shell. During the Linux startup process, klibc is loaded from within a temporary RAM file system, initramfs. It is inco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UClibc
__NOTOC__ In computing, uClibc (sometimes written µClibc) is a small C standard library intended for Linux kernel-based operating systems for embedded systems and mobile devices. uClibc was written to support μClinux, a version of Linux not requiring a memory management unit and thus suited for microcontrollers (uCs; the "u" is a Latin script typographical approximation - not a proper romanization, which would be letter "m" - of μ for "micro"). Development on uClibc started around 1999. uClibc was mostly written from scratch, but has incorporated code from glibc and other projects. The project lead is Erik Andersen, and the other main contributor is Manuel Novoa III. Licensed under the GNU Lesser General Public License, uClibc is free and open-source software. uClibc is much smaller than the glibc, the C library normally used with Linux distributions. While glibc is intended to fully support all relevant C standards across a wide range of hardware and kernel platforms, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glibc
The GNU C Library, commonly known as glibc, is the GNU Project's implementation of the C standard library. Despite its name, it now also directly supports C++ (and, indirectly, other programming languages). It was started in the 1980s by the Free Software Foundation (FSF) for the GNU operating system. Released under the GNU Lesser General Public License, glibc is free software. The GNU C Library project provides the core libraries for the GNU system, as well as many systems that use Linux as the kernel. These libraries provide critical APIs including ISO C11, POSIX.1-2008, BSD, OS-specific APIs and more. These APIs include such foundational facilities as open, read, write, malloc, printf, getaddrinfo, dlopen, pthread_create, crypt, login, exit and more. History The glibc project was initially written mostly by Roland McGrath, working for the Free Software Foundation (FSF) in the 1980s as a teenager. In February 1988, FSF described glibc as having nearly completed the func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C Standard Library
The C standard library or libc is the standard library for the C programming language, as specified in the ISO C standard.ISO/IEC (2018). '' ISO/IEC 9899:2018(E): Programming Languages - C §7'' Starting from the original ANSI C standard, it was developed at the same time as the C library POSIX specification, which is a superset of it. Since ANSI C was adopted by the International Organization for Standardization, the C standard library is also called the ISO C library. The C standard library provides macros, type definitions and functions for tasks such as string handling, mathematical computations, input/output processing, memory management, and several other operating system services. Application programming interface Header files The application programming interface (API) of the C standard library is declared in a number of header files. Each header file contains one or more function declarations, data type definitions, and macros. After a long period of stabi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
