Files_Notes.txt

Files

Need For Files

1. When You execute a particular program, its data is also lost  after execution.
2. So in order to persist the data or store the data even after the program exists, we can use Files
3. User can easily move the data from one computer to another using files.
4. In situations where the program requires large number of input, we can store all the input in a file and thus thereby reduce the time for input.

Definition
1. Files are defined as collection  of data.
2. This data is inter-related with each  other.

Types
1. Text Files
2. Binary Files

Differentiation
1. Text files are normal files that can be created using text and can be modifed easily. Binary  files are .bin files in the computer.
2. Text files contain readable data  whereas Binary files are  made  up of 0s and 1s and thus are difficult to read.  
3. Text files are less secure  compared to binary files.

Operations
1. Reading from a file.
2. Writing in a file.
3. Appending into a file.
4. Creating  a new file.
5. Deleting a file.
6. Renaming an existing file.
7. Compressing  a file.
8. Opening/Closing  a File.
9. Moving a file.

Modes
1. Read : r,rb
    if file exists, opened for Reading.
    if file doesn't exists, returns NULL
2. Write : w,rb
    if file exists, opened for Writing.
    if file doesn't exists, create a new file.
3. Append : a,rb
    if file exists, opened for Appending.
    if file doesn't exists, create a new file.
4. r+,rb+ : Read and  Write
5. w+,wb+ : Write
6. a+,ab+ : Append
*b-Binary*

File Functions
A. File Reading
	1. fgetc(<File Pointer>) : gets character by character from the file.
	2. fgets(<File Pointer>,<Size>,<Variable to store it in>) : gets String from the file.
	3. fread(<Variable>,sizeof(<Variable>),1,File Pointer) 
B. File Writing
	1. fputc()
	2. fputs()
	3. fwrite()