Overview

File Pointers

• File operations in C involve the use of file pointers, which are variables that hold the memory address of the file being accessed.

  FILE *filePointer;

Opening a File

• To open a file, use the fopen function. It requires the file path and the mode in which the file is opened (read, write, etc.).

  filePointer = fopen("example.txt", "r");

Closing a File

• Always close a file after operations using the fclose function. This ensures that resources are released.

  fclose(filePointer);

Reading from a File

• Use functions like fscanf or fgets to read data from a file.

  fscanf(filePointer, "%s", buffer);

Writing to a File

• Use functions like fprintf or fputs to write data to a file.

  fprintf(filePointer, "Hello, World!\n");

Error Handling

• Check if file operations are successful by verifying the return values of file functions.

  if (filePointer == NULL) { // Handle error }

File Modes

• Different modes dictate the type of file operations. Common modes include:

• "r" - Read

• "w" - Write (creates or truncates file)

• "a" - Append (creates or appends to file)

• "r+" - Read and Write

• "w+" - Read and Write (creates or truncates file)

Binary Files

• File I/O can be performed in binary mode ("rb", "wb", etc.) for non-text files.

  filePointer = fopen("binaryfile.bin", "rb");

Understanding file operations is crucial for handling data persistence in C. Whether reading data from a file, writing to it, or performing a combination of both, these file I/O operations enable efficient handling of external data.

If you have specific questions or if there are additional topics you'd like to explore, feel free to ask!