The printf project is a collaboration between Kingsley Emeka Umunna and Chibuzo Ashiegbu, actual students of Software Engineering at ALX Software Engineering Progromme , were a function named "_printf" imitates the actual "printf" command located in the stdio.h library. It contains some of the basic features and functions found in the manual 3 of "printf".
_printf() is a function that performs formatted output conversion and print data. Its prototype is the following:
int _printf(const char *format, ...)
Where format contains the string that is printed. As _printf() is variadic function, it can receives n arguments that replace by n tags written inside the string.
The format tags prototype is the following:
%[flags][length]specifier
If the program runs successfully, the return value is the amount of chars printed.
Specifier | Output |
---|---|
c | Character |
d or i | Signed decimal integer |
s | String of characters |
b | Signed binary |
o | Signed octal |
u | Unsigned integer |
x | Unsigned hexadecimal |
X | Unsigned hexadecimal (uppercase) |
p | Pointer address |
r | Reverse string of characters |
R | ROT13 translation of string |
S | String with special chars replaced by their ASCII value |
% | Character |
Flags | Description | Specifiers |
---|---|---|
+ | Prints a plus sign (+) when the argument is a positive number. In other case, prints a minus sign (-). | i, d |
(space) | Prints a blank space if the argument is a positive number | i, d |
# | Prints 0, 0x and 0X for o, x and X specifiers, respectively. It doesn't print anything if the argument is zero | o, x, X |
Length | Description | Specifiers |
---|---|---|
l | Prints a long int or unsigned long int | i, d, o, u, x and X |
h | Prints a short int or unsigned short int | i, d, o, u, x and X |
-
Printing the string of chars "Hello,ALX ":
- Use:
_printf("Hello ALX%s.", "ALX");
- Output:
Hello ALX .
- Use:
-
Printing an integer number:
- Use:
_printf("10 + 10 is equal to %d.", 20);
- Output:
10 + 10 is equal to 20.
- Use:
-
Printing a binary, octal and hexadecimal:
- Use:
_printf("10 in binary is [%b], in octal is [%o] and in hexadecimal is [%x]", 5, 5, 5);
- Output:
10 in binary is [1010], in octal is [12] and in hexadecimal is [A]
- Use:
-
Printing a string codified in ROT13:
- Use:
_printf("Hello in ROT13 is %R", "Hello");
- Output:
Hello in ROT13 is Urybb
- Use:
Using flags and length tags:
-
Printing the string of chars "Hello, ALX ":
- Use:
_printf("2 * 2 = %+d and 5 * -5 = %+i", 4, -25);
- Output:
2 * 2 = +4 and 5 * -5 = -25
- Use:
-
Printing a long integer number and short integer number:
- Use:
_printf("1 million as a long int is %ld, but as a short int is %hd", 1000000, 1000000);
- Output:
1 million as a long int is 1000000, but as a short int is 16960
- Use: