Operating Systems 2015F: Assignment 1

Please submit your answers to the following on CULearn. This assignment is due before class on September 23, 2015.

Choose the *most* accurate definition for the following terms/concepts:

system calls
function calls
library calls
process
fork
execve
file
filesystem
signal
library
kernel
environment variable
shell variable
zombie process

Definitions:

A system call that creates a new process by creating a logical copy of the current process.
The part of the operating system that runs in supervisor mode on the CPU and has the code that is run for all interrupts
A stream of bytes associated with a hierarchical name.
The API used by a process to access outside resources (disk/user input/network)
A variable that can only be accessed within the current shell.
A variable that can be accessed within the current process and in child processes (unless filtered).
A variable that can be accessed globally by all processes.
A process that has terminated but its parent has not retrieved its return value.
An indexed collection of object files that may be linked into a program.
A system call that loads an executable into the current process and runs it (erasing the process's old code and data).
A schedulable entity with its own CPU context that can share its memory with other schedulable entities.
A type of inter-process communication that is also used in UNIX to manage processes.
An invocation of code present inside of a process that was included when the program was compiled.
A system call that creates a new process, loads an executable, and runs it in the new process.
An invocation of code present inside of a process that was loaded into the process at runtime.
A system call to get the return value of a process that has terminated.
The main abstraction for running programs that gives each program its own memory and virtual CPU.
A hierarchical collection of key/value pairs, where the values are streams of bytes of arbitrary length.
A device for storing data.
The first process that runs on a UNIX-like system.

Solutions

fork: A system call that creates a new process by creating a logical copy of the current process.
kernel: The part of the operating system that runs in supervisor mode on the CPU and has the code that is run for all interrupts
file: A stream of bytes associated with a hierarchical name.
system calls: The API used by a process to access outside resources (disk/user input/network)
shell variables: A variable that can only be accessed within the current shell.
environment variables: A variable that can be accessed within the current process and in child processes (unless filtered).
(NONE): A variable that can be accessed globally by all processes.
zombie process: A process that has terminated but its parent has not retrieved its return value.
library: An indexed collection of object files that may be linked into a program.
execve: A system call that loads an executable into the current process and runs it (erasing the process's old code and data).
(NONE - thread): A schedulable entity with its own CPU context that can share its memory with other schedulable entities.
signals: A type of inter-process communication that is also used in UNIX to manage processes.
function call: An invocation of code present inside of a process that was included when the program was compiled.
(NONE - CreateProcess on Windows): A system call that creates a new process, loads an executable, and runs it in the new process.
library call: An invocation of code present inside of a process that was loaded into the process at runtime.
(NONE - wait): A system call to get the return value of a process that has terminated.
process: The main abstraction for running programs that gives each program its own memory and virtual CPU.
filesystem: A hierarchical collection of key/value pairs, where the values are streams of bytes of arbitrary length.
(NONE - disk?): A device for storing data.
(NONE - init): The first process that runs on a UNIX-like system.