This presentation introduces built-in functions in C programming. It defines built-in functions as functions provided by the C library that perform common tasks like file access, math operations, and graphics without needing to be defined by the programmer. It provides examples of commonly used built-in functions from header files like stdio.h for input/output, string.h for string manipulation, and math.h for math functions. The presentation concludes by noting advantages like code reusability but also potential disadvantages like increased complexity from functions.

1. WELCOME TO YOUR
PRESENTATION
Topic Name : Built in Function

2. PRESENTED BY
GroupMember ID
Tania Akter 0111-61-035
MD. Rayhanul Islam 0111-61-036
Saddam Hossain 0111-61-037

3. FUNCTION :
 A function is a group of statements that together perform
a task.
 A function is a block of code that performs a calculation
and returns a value.
 Every C program has at least one function, which
is main()

4. CLASSIFICATION OF FUNCTION :
User define
function
Library function
or Built-in function
Function

5. WHAT IS LIBRARY FUNCTION OR
BUILT-IN FUNCTION??
 Built in functions are the functions that are provided by
C library.
 These functions perform file access, mathematical
computations, graphics, memory management etc.
 Defined in a special header file.
 A function that is built into an application and can be
accessed by end-users.

6. BUILT-IN FUCTION HEADER FILES:
<stdio.h> : Standard input/output.
<conio.h> : This is console input/output header file.
<string.h> : All string related functions are defined in
this header file.
<math.h> : All maths related functions are defined
in this header file
<time.h> : Time and clock related functions

7. <STDIO.H> LIBRARY FUNCTIONS SOURCE CODE :
printf() : This function is used to print the character,
string, float, integer, octal and hexadecimal values onto
the output screen.
scanf() : This function is used to read a character,
string, numeric data from keyboard.
getc() : It reads character from file
gets() : It reads line from keyboard
getchar() : It reads character from keyboard
putchar() : It writes a character to screen

8. getw() : reads an integer from file
putw() : writes an integer to file
fgetc() : reads a character from file
putc() : writes a character to file
feof() : finds end of file
fprintf() : writes formatted data to a file
fscanf(): reads formatted data from a file
fgetchar : reads a character from keyboard
Fputchar : writes a character from keyboard

9. <CONIO.H> LBRARY FUNCTIONS SOURCE CODE :
clrscr() : This function is used to clear the output
screen.
getch() : It reads character from keyboard
textcolor() : This function is used to change the
text color
textbackground() : This function is used to
change text background

10. <STRING.H> LIBRARY FUNCTIONS SOURCE CODE:
strcat(str1, str2) : Concatenates str2 at the end of str1.
strcpy(str1, str2) : Copies str2 into str1
strlen(strl) : gives the length of str1.
strcmp(str1, str2) : Returns 0 if str1 is same as
str2. Returns <0 if strl < str2. Returns >0 if str1 > str2.
strdup() : duplicates the string
strlwr() : converts string to lowercase

11. <MATH.H> LIBRARY FUNCTIONS SOURCE CODE :
sin( ) : This function is used to calculate sine value.
cos( ) : This function is used to calculate cosine.
tan( ) : This function is used to calculate tangent.
log( ) : This function is used to calculates natural
logarithm.
pow( ) : This is used to find the power of the given
number.

12. <TIME.H> LIBRARY FUNCTIONS SOURCE CODE :
setdate() : This function used to modify the system date
getdate() : This function is used to get the CPU time
clock() : This function is used to get current system time
time() : This function is used to get current system time
as structure
difftime() : This function is used to get the difference
between two given times

13. ADVANTAGES :
 It helps in making the code very simple and much
more easier to handle.
 A function may be used by many other programs.
 You can use it over and over without retyping the
code
 Less code for more
 Helps organize your code

14. DISADVANTAGES:
 I think functions are sometimes difficult to handle
and can confuse the programmer in handling
different tasks.

15. PROGRAMING IN BUILT-IN FUNCTION :
#include<stdio.h>
main()
{
printf ("Welcome To Your Presentation");
}
Sample Output :

16. THANK YOU