International Journal For Technological Research In Engineering Volume 3, Issue 3, November-2015 ISSN (Online): 2347 - 4718 ANDROID FRAMEWORK Saksham Wason Dronacharya College of Engineering, Gurgaon, India Abstract: Abstract Android is a mobile operating directories for easy navigation and usage. These directories system (OS) currently developed by Google, based on may contain files and other directions. OS Keeps track of the Linux kernel and designed primarily for touch information, location, uses, status etc. The collective screen mobile devices such as smart phones and tablets. facilities are often known as file system. It Decides who gets Android's user interface is based on direct manipulation, the resources and also allocates and de-allocates the using touch gestures that loosely correspond to real-world resources. actions, such as swiping, tapping and pinching, to manipulate on-screen objects, along with a virtual II. INTRODUCTION TO VIRTUAL OPERATING keyboard for text input. In addition to touchscreen devices, SYSTEM Google has further developed Android TV for The idea of a virtual operating system is to provide standard televisions, Android Auto for cars, and Android Wear for versions of the following- wrist watches, each with a specialized user interface. 1.Operating system primitives accessible through Variants of Android are also used on notebooks, game programming languages consoles, digital cameras, and other electronics. As of 2015, 2. The utility programs such as compilers, linkers and editors Android has the largest installed base of all operating 3. The command language or means by which users access systems. system resources from a terminal based on organizational requirements. I. INTRODUCTION OF OPERATING SYSTEM (OS) An operating system is a software program that enables the VM (operating system) computer hardware to communicate and operate with the Introduction: computer software. Without a computer operating system, a VM (often: VM/CMS) is a family of computer and software programs would be useless. IBM virtual machine operating systems used on IBM Application programs usually require an operating system to mainframes System/370, System/390, zSeries, System z and function. The operating system provides two main functions. compatible systems, including the Hercules emulator for The first function is managing the basic hardware operations. personal computers. The first version, released in 1972, was The control of input and output, storage space, detecting VM/370, or officially Virtual Machine Facility/370. This equipment failure, and management of storage are just some was a System/370 reimplementation of earlier CP/CMS of the responsibilities of the Operating System. The second operating system. Milestone versions included VM/SP.The function is managing and interacting with the applications current version, z/VM, is still widely used as one of the main software. It takes over the tasks of printing and saving data. full virtualization solutions mainframe market. To provide an environment for a computer user to execute Overview: programs. The heart of the VM architecture is a control program or Basic Function of OS: hypervisor called VM-CP (usually: CP; sometimes, Process Management: The Operating System also Treats ambiguously: VM). It runs on the physical hardware, and the Process Management means all the Processes those are creates the virtual machine environment. VM-CP provides given by the user or the Process those are System's own full virtualization of the physical machine – including I/O Process are Handled by the Operating System. The Operating and other privileged operations. It performs system's System will Create the Priorities for the user and also Start or resource-sharing, including device management, dispatching, Stops the Execution of the Process and Also Makes the Child virtual storage management, and other traditional operating Process after dividing the Large Processes into the Small system tasks. Each VM user is provided with a separate Processes. virtual machine having its own address space, virtual Memory Management: Operating System also manages the devices, etc., and which is capable of running any software Memory of the Computer System means provide the Memory that could be run on a stand- alone machine. A given VM to the Process and Also deallocate the Memory from the mainframe typically runs hundreds or thousands of virtual Process. And also defines that if a Process gets completed machine instances. VM-CP began life as CP-370, a then this will deallocate the Memory from the Processes. reimplementation of CP-67, itself a reimplementation of CP- Device Management: OS manages device communication via 40. their respective drivers. It Allocates and De-allocates the Running within each virtual machine is another, "guest" device in the efficient way. It also decides which process gets operating system. This might be: the device when and for how much time. CMS ("Conversational Monitor System", renamed from the File Management: A file system is normally organized into "Cambridge Monitor System" of CP/CMS). Its official name www.ijtre.com Copyright 2015.All rights reserved. 443 International Journal For Technological Research In Engineering Volume 3, Issue 3, November-2015 ISSN (Online): 2347 - 4718 is VM- CMS (confusing, since VM is commonly called VM remained an important platform within IBM, used for VM/CMS). Most virtual machines run CMS, a lightweight, operating system development and time- sharing use; but for single-user operating system. Its interactive environment is customers it remained IBM's "other operating system". The comparable to that of a single-user PC, including a file OS and DOS families remained IBM's strategic products, system, programming services, device access, and command- and customers were not encouraged to run VM. Those a that line processing. did formed close working relationships, continuing the A mainstream operating system. IBM's mainstream operating community-support model of early CP/CMS users. In the systems (i.e. the MVS or DOS/VSE families) can be loaded meantime, the system struggled with political infighting and run without modification. The VM hypervisor treats within IBM over what resources should be available to the guest operating systems as application programs with project, as compared with other IBM efforts. A basic has exceptional privileges – it prevents them from using "problem" with the system was seen at IBM's field sales privileged instructions but simulates privileged instructions level: VM/CMS demonstrably reduced the amount of on their behalf. Most mainframe operating systems terminate hardware needed to support a given a normal application which tries to usurp the operating system's privileges. Virtual Memory: A Virtual Memory has the advantage of Another copy of VM. A "second level" instance of VM can allowing more processes to run than the allowed memory be fully virtualized inside virtual machine. This is how VM size. This is achieved by only including parts of processes development and testing is done. (A "second- level" VM can that are necessary to run in memory and the rest on disk. The potentially implement a different virtualization of the absolute minimum part of a process that must always be in hardware. This technique was used to develop S/370 software memory is called its working set. Usually, a program doesn't before S/370 hardware was available, and it continued to play need to have its entire binary file in memory to run when it is a role in new hardware development at IBM. The literature performing a task that only uses part of its file. What this cites practical examples of virtualization five levels deep. means is that, say, a 16MB program could happily run on a Levels of VM below the top are also for the treated as machine with only 4MB of memory. applications but with exceptional privileges. A copy of the mainframe version of AIX or Linux. In the Virtual Machine: A virtual machine (VM) is a software mainframe environment, these operating systems often run implementation of a machine (for example, a computer) that under VM, and are handled like other guest operating executes programs like a physical machine. A virtual systems. A specialized VM subsystem. Several non- CMS machine is a completely isolated guest operating system systems run within VM-CP virtual machines, providing installation within a normal host operating system. Virtual services to CMS users all such as spooling, intercrosses Machine Operating System creates illusion of multiple communications, the and specialized device support. They processors each capable of executing independently. Virtual operate "behind the scenes", extending the services available machines are separated into two major categories, based on to CMS without adding to the VM- CP control program. By their use and degree of correspondence to any real machine:- running in separate virtual machines, they receive the same security and reliability protections as other VM users. System Virtual Machines: A system virtual machine provides a complete system platform which supports the Examples include: execution of a complete operating system. These usually RSCS ("Remote Spooling and Communication emulate an existing architecture, and are built with the Subsystem", aka VNET) - communication and information purpose of either providing a platform to run programs transfer facilities between virtual machines where the real hardware is not available for use or of having RACF ("Resource