Escape Sequences , Data types & Format Specifiers

Escape Sequences:

• Escape Sequences are used to format the output from a print function.
• The escapes sequences are character literals or character constants.
• Every escape sequence character starts with a backward slash(\)
• Though it is a combination of \ and another letter (two characters), it is treated as a single character.

Escape Sequences in C

Character	Name	Use
\n	New line	Move the cursor to next line
\t	Tab Space	Insert a single Tab Space
\a	Alert	Generates a Beep Sound
\b	Back Space	Cursor is moved one character back
\r	Carraige Return	Cursor moved to starting of the same line
\\	Forward Slash	Insert a single \
\"	Double quote	Insert a single "

Data Types and Format Specifiers:

Variable:

• Variable is defined to be named memory location
• A single variable can hold a single data value only
• If the variable is already having a value an a new value is given, then the new value replaces the old value.
• Variable named should be chosen by the programmer and should obey identifier rules (Ref Chap-1 Introduction to C)

Data Types:

• The data type is defined to be a keyword that defines the type of data that a variable can hold.
• The flow chart below gives a clear view of data types in C:

System Defined Data Types

Name	Keyword	Format Specifier	Memory	Range
Void	void	---	0 bytes	Nothing
Character	char	%c	1 byte	Any Ascii Character
Integer	int	%d	2 bytes	-32768 to 32768
Float	float	%f	4 bytes	3.4*10^-38 to 3.4*10^38
Double	double	%lf	8 bytes	1.7*10^-308 to 1.7*10^308

Type Qualifiers:

Type Qualifier is a special keyword that can control the basic data to an increased range or to a decreased range slightly.