Concept
Fork (system call)
Related concepts (17)
Unistd.h
In the C and C++ programming languages, unistd.h is the name of the that provides access to the POSIX operating system API. It is defined by the POSIX.1 standard, the base of the Single Unix Specification, and should therefore be available in any POSIX-compliant operating system and compiler. For instance, this includes Unix and Unix-like operating systems, such as GNU variants, distributions of Linux and BSD, and macOS, and compilers such as GCC and LLVM. On Unix-like systems, the interface defined by unistd.
Environment variable
An environment variable is a user-definable value that can affect the way running processes will behave on a computer. Environment variables are part of the environment in which a process runs. For example, a running process can query the value of the TEMP environment variable to discover a suitable location to store s, or the HOME or USERPROFILE variable to find the directory structure owned by the user running the process.
Kernel (operating system)
The kernel is a computer program at the core of a computer's operating system and generally has complete control over everything in the system. It is the portion of the operating system code that is always resident in memory and facilitates interactions between hardware and software components. A full kernel controls all hardware resources (e.g. I/O, memory, cryptography) via device drivers, arbitrates conflicts between processes concerning such resources, and optimizes the utilization of common resources e.
Dynamic linker
In computing, a dynamic linker is the part of an operating system that loads and links the shared libraries needed by an executable when it is executed (at "run time"), by copying the content of libraries from persistent storage to RAM, filling jump tables and relocating pointers. The specific operating system and executable format determine how the dynamic linker functions and how it is implemented.
Daemon (computing)
In multitasking computer operating systems, a daemon (ˈdiːmən or ˈdeɪmən) is a computer program that runs as a background process, rather than being under the direct control of an interactive user. Traditionally, the process names of a daemon end with the letter d, for clarification that the process is in fact a daemon, and for differentiation between a daemon and a normal computer program. For example, is a daemon that implements system logging facility, and is a daemon that serves incoming SSH connections.
Process (computing)
In computing, a process is the instance of a computer program that is being executed by one or many threads. There are many different process models, some of which are light weight, but almost all processes (even entire virtual machines) are rooted in an operating system (OS) process which comprises the program code, assigned system resources, physical and logical access permissions, and data structures to initiate, control and coordinate execution activity.
C shell
The C shell (csh or the improved version, tcsh) is a Unix shell created by Bill Joy while he was a graduate student at University of California, Berkeley in the late 1970s. It has been widely distributed, beginning with the 2BSD release of the Berkeley Software Distribution (BSD) which Joy first distributed in 1978. Other early contributors to the ideas or the code were Michael Ubell, Eric Allman, Mike O'Brien and Jim Kulp. The C shell is a command processor which is typically run in a text window, allowing the user to type and execute commands.