Types of operating systems

Real-time

A real-time operating system is a multitasking operating system that aims at executing real-time applications. Real-time operating systems often use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. The main objective of real-time operating systems is their quick and predictable response to events. They have an event-driven or time-sharing design and often aspects of both. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.

Multi-user

A multi-user operating system allows multiple users to access a computer system at the same time. Time-sharing systems and Internet servers can be classified as multi-user systems as they enable multiple-user access to a computer through the sharing of time. Single-user operating systems have only one user but may allow multiple programs to run at the same time.

Multi-tasking vs. single-tasking

A multi-tasking operating system allows more than one program to be running at the same time, from the point of view of human time scales. A single-tasking system has only one running program. Multi-tasking can be of two types: pre-emptive and co-operative. In pre-emptive multitasking, the operating system slices the CPU time and dedicates one slot to each of the programs. Unix-like operating systems such as Solaris and Linux support pre-emptive multitasking, as does AmigaOS. Cooperative multitasking is achieved by relying on each process to give time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking. 32-bit versions of both Windows NT and Win9x, used pre-emptive multi-tasking. Mac OS prior to OS X used to support cooperative multitasking.

Distributed

A distributed operating system manages a group of independent computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine. When computers in a group work in cooperation, they make a distributed system.

Embedded

Embedded operating systems are designed to be used in embedded computer systems. They are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources. They are very compact and extremely efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems.

Internet: <http://en.wikipedia.org> (adapted).

Based on the text above, judge the following item.

Systems that use time-sharing are not considered to be multiuser systems, since they do not allow the simultaneous access of several users to a computer.

Types of operating systems

Real-time

A real-time operating system is a multitasking operating system that aims at executing real-time applications. Real-time operating systems often use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. The main objective of real-time operating systems is their quick and predictable response to events. They have an event-driven or time-sharing design and often aspects of both. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.

Multi-user

A multi-user operating system allows multiple users to access a computer system at the same time. Time-sharing systems and Internet servers can be classified as multi-user systems as they enable multiple-user access to a computer through the sharing of time. Single-user operating systems have only one user but may allow multiple programs to run at the same time.

Multi-tasking vs. single-tasking

A multi-tasking operating system allows more than one program to be running at the same time, from the point of view of human time scales. A single-tasking system has only one running program. Multi-tasking can be of two types: pre-emptive and co-operative. In pre-emptive multitasking, the operating system slices the CPU time and dedicates one slot to each of the programs. Unix-like operating systems such as Solaris and Linux support pre-emptive multitasking, as does AmigaOS. Cooperative multitasking is achieved by relying on each process to give time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking. 32-bit versions of both Windows NT and Win9x, used pre-emptive multi-tasking. Mac OS prior to OS X used to support cooperative multitasking.

Distributed

A distributed operating system manages a group of independent computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine. When computers in a group work in cooperation, they make a distributed system.

Embedded

Embedded operating systems are designed to be used in embedded computer systems. They are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources. They are very compact and extremely efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems.

Internet: <http://en.wikipedia.org> (adapted).

Based on the text above, judge the following item.

Since the first release of Windows NT, no version of Windows used cooperative multi-tasking.

Types of operating systems

Real-time

A real-time operating system is a multitasking operating system that aims at executing real-time applications. Real-time operating systems often use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. The main objective of real-time operating systems is their quick and predictable response to events. They have an event-driven or time-sharing design and often aspects of both. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.

Multi-user

A multi-user operating system allows multiple users to access a computer system at the same time. Time-sharing systems and Internet servers can be classified as multi-user systems as they enable multiple-user access to a computer through the sharing of time. Single-user operating systems have only one user but may allow multiple programs to run at the same time.

Multi-tasking vs. single-tasking

A multi-tasking operating system allows more than one program to be running at the same time, from the point of view of human time scales. A single-tasking system has only one running program. Multi-tasking can be of two types: pre-emptive and co-operative. In pre-emptive multitasking, the operating system slices the CPU time and dedicates one slot to each of the programs. Unix-like operating systems such as Solaris and Linux support pre-emptive multitasking, as does AmigaOS. Cooperative multitasking is achieved by relying on each process to give time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking. 32-bit versions of both Windows NT and Win9x, used pre-emptive multi-tasking. Mac OS prior to OS X used to support cooperative multitasking.

Distributed

A distributed operating system manages a group of independent computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine. When computers in a group work in cooperation, they make a distributed system.

Embedded

Embedded operating systems are designed to be used in embedded computer systems. They are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources. They are very compact and extremely efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems.

Internet: <http://en.wikipedia.org> (adapted).

Based on the text above, judge the following item.

Only rarely, operating systems use specific scheduling algorithms that make sure that the programs behave in a deterministic way.

Types of operating systems

Real-time

A real-time operating system is a multitasking operating system that aims at executing real-time applications. Real-time operating systems often use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. The main objective of real-time operating systems is their quick and predictable response to events. They have an event-driven or time-sharing design and often aspects of both. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.

Multi-user

A multi-user operating system allows multiple users to access a computer system at the same time. Time-sharing systems and Internet servers can be classified as multi-user systems as they enable multiple-user access to a computer through the sharing of time. Single-user operating systems have only one user but may allow multiple programs to run at the same time.

Multi-tasking vs. single-tasking

A multi-tasking operating system allows more than one program to be running at the same time, from the point of view of human time scales. A single-tasking system has only one running program. Multi-tasking can be of two types: pre-emptive and co-operative. In pre-emptive multitasking, the operating system slices the CPU time and dedicates one slot to each of the programs. Unix-like operating systems such as Solaris and Linux support pre-emptive multitasking, as does AmigaOS. Cooperative multitasking is achieved by relying on each process to give time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking. 32-bit versions of both Windows NT and Win9x, used pre-emptive multi-tasking. Mac OS prior to OS X used to support cooperative multitasking.

Distributed

A distributed operating system manages a group of independent computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine. When computers in a group work in cooperation, they make a distributed system.

Embedded

Embedded operating systems are designed to be used in embedded computer systems. They are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources. They are very compact and extremely efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems.

Internet: <http://en.wikipedia.org> (adapted).

Based on the text above, judge the following item.

Single-user operating systems do not allow the use of a computer by multiple users. Moreover, they do not allow more than one program to run at the same time.

Types of operating systems

Real-time

A real-time operating system is a multitasking operating system that aims at executing real-time applications. Real-time operating systems often use specialized scheduling algorithms so that they can achieve a deterministic nature of behavior. The main objective of real-time operating systems is their quick and predictable response to events. They have an event-driven or time-sharing design and often aspects of both. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.

Multi-user

A multi-user operating system allows multiple users to access a computer system at the same time. Time-sharing systems and Internet servers can be classified as multi-user systems as they enable multiple-user access to a computer through the sharing of time. Single-user operating systems have only one user but may allow multiple programs to run at the same time.

Multi-tasking vs. single-tasking

A multi-tasking operating system allows more than one program to be running at the same time, from the point of view of human time scales. A single-tasking system has only one running program. Multi-tasking can be of two types: pre-emptive and co-operative. In pre-emptive multitasking, the operating system slices the CPU time and dedicates one slot to each of the programs. Unix-like operating systems such as Solaris and Linux support pre-emptive multitasking, as does AmigaOS. Cooperative multitasking is achieved by relying on each process to give time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking. 32-bit versions of both Windows NT and Win9x, used pre-emptive multi-tasking. Mac OS prior to OS X used to support cooperative multitasking.

Distributed

A distributed operating system manages a group of independent computers and makes them appear to be a single computer. The development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine. When computers in a group work in cooperation, they make a distributed system.

Embedded

Embedded operating systems are designed to be used in embedded computer systems. They are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources. They are very compact and extremely efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems.

Internet: <http://en.wikipedia.org> (adapted).

Based on the text above, judge the following item.

In an event-driven system, the switching between tasks is triggered by clock interrupts, and the duration of each time slice is always the same.

The aging process affects us all at different rates. Some people of fifty-three, like the esteemed author, look a mere thirty-five, with sparkling brown eyes, a handsome gait and the virility of a steam train. Others, like the author’s friend Colin, look like little middle-aged men at twenty-one with middle-aged outlooks of set ways and planned futures. In women the former condition is common but women rarely suffer from the latter, being fired with the insatiable drive of ambition for either an independent and distinguished career in a still male-dominated world, or a home and seven children by the time they are thirty followed by an independent and distinguished career as a Cheltenham councillor or a public relations agent for Jonathan Cape, in later life.

No such luck for Charles Charlesworth, who was born on the 14th of March, 1829, in Stafford. At the age of four Charles had a beard and was sexually active.

In the final three years of his life his skin wrinkled, he developed varicose veins, shortness of breath, grey hair, senile dementia and incontinence. Some time in his seventh year he fainted and never gained consciousness.

The coroner returned a verdict of natural causes due to old age.

Hugh Cory. Advanced writing with english in use. Oxford University Press, p. 34.

According to the text above,

Charles Charlesworth’s cause of death was old age although he was only seven.

Comigo exerceu com calma ferocidade o seu sadismo. Na minha ânsia de ler, eu nem notava as humilhações a que ela me submetia: continuava a implorar-lhe emprestados os livros que ela não lia.

Até que veio para ela o magno dia de começar a exercer sobre mim uma tortura chinesa. Como casualmente, informou-me que possuía As Reinações de Narizinho, de Monteiro Lobato.

Era um livro grosso, meu Deus, era um livro para se ficar vivendo com ele, comendo-o, dormindo-o. E completamente acima de minhas posses. Disse-me que eu passasse pela sua casa no dia seguinte e que ela o emprestaria.

Até o dia seguinte eu me transformei na própria esperança de alegria: eu não vivia, nadava devagar em um mar suave, as ondas me levavam e me traziam. No dia seguinte, fui à sua casa, literalmente correndo. Não me mandou entrar. Olhando bem para meus olhos, disse-me que havia emprestado o livro a outra menina, e que eu voltasse no dia seguinte para buscá-lo. Boquiaberta, saí devagar, mas em breve a esperança de novo me tomava toda e eu recomeçava na rua a andar pulando, que era o meu modo estranho de andar pelas ruas de Recife. Dessa vez nem caí: guiava-me a promessa do livro, o dia seguinte viria, os dias seguintes seriam mais tarde a minha vida inteira, o amor pelo mundo me esperava, andei pulando pelas ruas como sempre e não caí nenhuma vez.

Clarice Lispector. Felicidade clandestina. In: Felicidade clandestina: contos. Rio de Janeiro: Rocco, 1998 (com adaptações).

Julgue o próximo item, referente às ideias e às estruturas linguísticas do texto acima.

A oração introduzida pelo pronome “que” tem caráter restritivo, visto que especifica a ação expressa pela locução “andar pulando”.

Texto para o item

A inércia da vida real desaparece magicamente na navegação pelo ciberespaço, desprovida de fricção. No mercado atual, encontramos uma série de produtos privados de suas propriedades malignas: café sem cafeína, creme sem gordura, cerveja sem álcool… ciberespaço. A realidade virtual simplesmente generaliza esse procedimento: cria uma realidade privada de substância. Da mesma maneira que o café descafeinado tem cheiro e gosto semelhantes aos do café, sem ser café, minha persona na rede é sempre um “eu” descafeinado. Por outro lado, existe também o excesso oposto, e muito mais perturbador: o excedente de minha persona virtual com relação ao meu “eu” real. Nossa identidade social, a pessoa que presumimos ser em nosso intercurso social, já é uma máscara, já envolve a repressão de nossos impulsos inadmissíveis; e é precisamente nessas condições de “só uma brincadeira”, quando as regras que regulam os intercâmbios de nossas vidas reais estão temporariamente suspensas, que podemos nos permitir a exibição dessas atitudes reprimidas.

O fato de que eu perceba minha autoimagem virtual como simples brincadeira me permite, assim, suspender os obstáculos que usualmente impedem que eu realize meu “lado escuro” na vida real — meu “id eletrônico” ganha asas dessa forma. E o mesmo se aplica aos meus parceiros na comunicação via ciberespaço. Não há como ter certeza de quem sejam, de que sejam “realmente” como se descrevem, ou de saber se existe uma pessoa “real” por trás da persona online. A persona online é uma máscara para uma multiplicidade de pessoas? A pessoa “real” com quem converso possui e manipula mais personas no computador, ou estou simplesmente me relacionando com uma entidade digitalizada que não representa pessoa “real” alguma?

Slavoj Zizek. Identidades vazias. Internet: <http://slavoj-zizek.blogspot.com.br> (com adaptações).

A partir das ideias desenvolvidas no texto, julgue o item a seguir.

O texto evidencia a dualidade do ciberespaço, decorrente da possibilidade de o usuário utilizá-lo tanto para esconder sua verdadeira identidade quanto para exacerbar pensamentos e atitudes que, no intercâmbio de sua vida social, ele não se permita expor.

Comigo exerceu com calma ferocidade o seu sadismo. Na minha ânsia de ler, eu nem notava as humilhações a que ela me submetia: continuava a implorar-lhe emprestados os livros que ela não lia.

Até que veio para ela o magno dia de começar a exercer sobre mim uma tortura chinesa. Como casualmente, informou-me que possuía As Reinações de Narizinho, de Monteiro Lobato.

Era um livro grosso, meu Deus, era um livro para se ficar vivendo com ele, comendo-o, dormindo-o. E completamente acima de minhas posses. Disse-me que eu passasse pela sua casa no dia seguinte e que ela o emprestaria.

Até o dia seguinte eu me transformei na própria esperança de alegria: eu não vivia, nadava devagar em um mar suave, as ondas me levavam e me traziam. No dia seguinte, fui à sua casa, literalmente correndo. Não me mandou entrar. Olhando bem para meus olhos, disse-me que havia emprestado o livro a outra menina, e que eu voltasse no dia seguinte para buscá-lo. Boquiaberta, saí devagar, mas em breve a esperança de novo me tomava toda e eu recomeçava na rua a andar pulando, que era o meu modo estranho de andar pelas ruas de Recife. Dessa vez nem caí: guiava-me a promessa do livro, o dia seguinte viria, os dias seguintes seriam mais tarde a minha vida inteira, o amor pelo mundo me esperava, andei pulando pelas ruas como sempre e não caí nenhuma vez.

Clarice Lispector. Felicidade clandestina. In: Felicidade clandestina: contos. Rio de Janeiro: Rocco, 1998 (com adaptações).

Julgue o próximo item, referente às ideias e às estruturas linguísticas do texto acima.

A partir do trecho “os dias seguintes seriam mais tarde a minha vida inteira”, é correto inferir que, em sua vida adulta, a personagem continuou dependente do empréstimo de livros de terceiros.

Lucas e Dimas são amigos de infância e, hoje, apesar de estarem distantes um do outro, sempre mantêm contato via rádio, como na conversa transcrita a seguir, em que eles utilizaram o Código Internacional Q.

Lucas: — Oi, Dimas, tudo bem?

Dimas: — Tudo ótimo. Preciso falar contigo. Informe QRD.

Lucas: — Lamento, Dimas, mas não posso dizer via rádio, pois agora estou trabalhando em uma atividade sigilosa. Tenho de me cuidar. Fiquei sabendo que vai sair um QSJ pra você?

Dimas: — QSL, Lucas, NIL ainda. Estamos aguardando. Nada confirmado. Informe QSA. Por aqui 5.5, QRX. Acabei de tropeçar em uma pedra.

Lucas: — Dimas, você sempre foi distraído. Olhe por onde anda! Está fazendo um QRF após seu trabalho?

Dimas: — Não entendi. QSB, Lucas.

Lucas: — Desculpe-me, Dimas, vou fazer um QRS. Assim ficará melhor. QSL?

Dimas: — QSL. Avance, Lucas.

Lucas: — Não tinha dito nada demais, Dimas.

Dimas: — Estava andando rápido pra chegar ao meu serviço.

Lucas: — Dimas, você trabalha num lugar privilegiado.

Dimas: — Você também, Lucas. Espero que um dia possamos levar QUA positivas a todos. Tenho de ir, QTO, sabe como é, né?

Lucas: — Ok, QSL na QTC.

Dimas: — TKS.

Com base no diálogo acima reproduzido, julgue o item que se segue, à luz do Código Internacional Q.

Nas últimas falas, Dimas disse que precisava sair para uma reunião – “QTO” (l.15) –, Lucas respondeu ter compreendido a mensagem – “QSL” seguido de “QTC”, ambos na linha 16 –, e Dimas, com um agradecimento – “TKS” (l.17) –, terminou a conversação.