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ReadFileRead File
Last edited time
Apr 29, 2024 2:22 PM
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👉 Overview
👀 What ?
Reading a file using the 'read' function is a common operation in many programming languages. The 'read' function allows a program to access and process data stored in external files, which can be text files, binary files, image files, etc.
🧐 Why ?
Reading files is fundamental to many applications. It allows programs to access large amounts of data, configurations, or user-generated content that is stored externally. Without the ability to read files, programs would be limited to only using data that is hard-coded into the program or input directly from the user.
⛏️ How ?
To read a file, you must first open it. This is usually done using a 'open' function, which returns a file object. Then, you can use the 'read' function on the file object to read the file's contents. Depending on the language, the 'read' function may return the entire contents of the file as a single string, or it may return a list of lines. Once you're done with the file, you should always close it using the 'close' function to free up system resources.
⏳ When ?
File reading operations are used whenever a program needs to access external data. This could be when the program starts up, when the user performs certain actions, or at regular intervals. The timing depends on the specific needs of the program.
⚙️ Technical Explanations
The 'read' function works by interacting with the operating system's file handling APIs. It takes a file descriptor (which is obtained when the file is opened) and a buffer (which is a block of memory allocated by the program). The operating system fills the buffer with data from the file, and then the 'read' function returns this data to the program. The program can then process the data in whatever way it needs to. Reading files is a relatively slow operation, as it involves disk I/O, so programs often use techniques like buffering or asynchronous I/O to improve performance.