File Processing

Question 1

Files are used for data persistence which is…

Answer 1

Permanent retention of data

Question 2

How do computers store files?

Answer 2

Secondary storage devices

Question 3

What is a file?

Answer 3

A sequence of bytes

Question 4

Files end with

Answer 4

End-of-file marker
Or
Specific byte number recorded in data structure

Question 5

What happens when a file is opened?

Answer 5

An object is created with associated stream

Question 6

Which headers must be included for file processing?

Answer 6

<iostream> and <fstream>
</fstream></iostream>

Question 7

<fstream>'s typedef aliases enables....
</fstream>

Answer 7

char output to files

Question 8

C++ structure on file

Answer 8

Not imposed

Question 9

When an ____________ object is created, a file can be opened for output

Answer 9

ofstream

Question 10

What happens to existing files opened with iOS::out?

Answer 10

They are truncated

Question 11

How can you add to the end of a file?

Answer 11

ios::app

Question 12

ofstream objects must be created while opening a file

Answer 12

No, it can be attached later

Question 13

What does overloaded operator ! do for a stream?

Answer 13

Determines if it is opened correctly

Question 14

What is the failbit for cin?

Answer 14

End-of-file indicator

Question 15

How can you close a stream object?

Answer 15

Use close member function or stream object’s destructor

Question 16

Why do files store data?

Answer 16

So it can be received for processing when needed

Question 17

When are objects of ifstream opened for input?

Answer 17

By default

Question 18

How do you retrieve data sequentially from a file?

Answer 18

Read from the beginning until desired data is found

Question 19

What is the file position pointer for ifstream?

Answer 19

seekg

Question 20

What is the file position pointer for ostream?

Answer 20

seekp

Question 21

How can you indicate the byte number in a file where next input will occur?

Answer 21

get pointer for istream
put pointer for ostream

Question 22

Which three seek directions can seekg indicate?

Answer 22

ios::beg
ios::cur
ios::end

Question 23

File position pointer specifies the location as number of bytes from file’s start location or it’s….

Answer 23

offset

Question 24

What member functions return the current locations of the get and put pointers?

Answer 24

tellg and tellp

Question 25

Why can you not modify data that is formatted and written to a sequential file?

Answer 25

Record sizes can vary

Question 26

What is an instant access application?

Answer 26

When a particular record must be located immediately

Question 27

What makes instant access to file possible?

Answer 27

random access files

Question 28

How do you format files for random access?

Answer 28

Same size, fixed length records

Question 29

What are the advantages of random access files?

Answer 29

Data can be inserted, updated, or deleted without rewriting the entire file

Question 30

Which ostream member function outputs a fixed number of bytes, beginning at a specific location in memory, to a stream?

Answer 30

write

Question 31

Which istream member function inputs a fixed number of bytes from the specified stream to an area in memory beginning at a specified address specified by get file position pointer?

Answer 31

read

Question 32

How does function write find location to output?

Answer 32

Takes const char* of bytes

Question 33

How to convert a pointer of one type to a pointer of an unrelated type?

Answer 33

reinterpret_cast

Question 34

How can unformatted data be compiled and executed?

Answer 34

Must be on a system compatible with the program that wrote the data

Question 35

Objects of class string do not have uniform size, instead they use….

Answer 35

Dynamically allocated memory