14. Files and Streams
Computer programming involves not only manipulating data in memory, but also reading and writing data to files. In simple terms, a file is a location on disk where a group of related data is stored. File programming is an essential part of software programming as it provides mechanisms to store user data for future use.
In programming, a stream is a sequence of data. There are two main types of streams: input streams that read data from disk to memory, and output streams that write data from memory to disk.
Files in Programming Logic
Files are used to store data in a non-volatile format such as text or binary format. They are especially useful in programs that require large amounts of information to be input or output. For example, a program that handles payroll information will likely use files to store employee information rather than entering all of the information each time the program runs.
To use files, a program must open the file, perform reads or writes, and then close the file. Opening a file tells the operating system that certain file operations are about to be performed. The operating system, in turn, ensures that the file exists and is available for use.
Streams in Logic Programming
A stream is an abstraction that represents a sequence of bytes. There are two types of streams: input stream and output stream. An input stream is used to read data from a source (like a file), an output stream is used to write data to a destination (like a file).
An input stream reads bytes of data from a source, one byte at a time. For example, an input stream can be used to read data from a text file, receive data from a network connection, or get data from the keyboard. An output stream writes data to a destination one byte at a time. For example, an output stream can be used to write data to a text file, send data over a network connection, or display data on the screen.
Operations with Files and Streams
Basic operations that can be performed on a file include: opening a file, reading a file, writing to a file, and closing a file. Likewise, operations that can be performed on a stream include: opening a stream, reading from a stream, writing to a stream, and closing a stream.
To open a file in a program, you need to specify the file name and opening mode. Open mode can be read (r), write (w) or append (a). Once the file is opened, you can read or write the file depending on the opening mode. When you are done with the file, you must close it to release system resources.
To open a stream, you need to specify the source or destination of the stream. Once the stream is opened, you can read or write to the stream. When you are done with the stream, you must close it to release system resources.
Conclusion
In summary, files and streams are fundamental in programming logic. They allow programs to store data non-volatilely and handle large amounts of data efficiently. Learning to work with files and streams is an important step towards becoming a competent programmer.
It is therefore essential to understand and master the concept of files and streams when learning programming logic. Not only will this help create more efficient and effective programs, it will also open the door to exploring more advanced and complex concepts in programming.
