File pointers are special variables of type FILE * used to access and control file operations in C. When a file is opened using fopen(), it returns a file pointer that acts as a handle to the opened file. This pointer is used in all subsequent operations like reading, writing, and closing the file.

It keeps track of the current position in the file so that you don’t need to manually manage where to read or write next. File pointers are essential for sequential access, meaning the program processes the file from beginning to end unless otherwise directed. You can also use functions like fseek() to move the pointer to a specific location in the file, ftell() to get the current position, and rewind() to move back to the beginning.

These pointer-based operations make file management more flexible and efficient. Without file pointers, it would be difficult to manage multiple files or perform non-linear access.

Example:

FILE *fp;

fp = fopen(“data.txt”, “w”);

if (fp != NULL) {

fprintf(fp, “Hello, world!”);

fclose(fp);

}