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_printf

_printf is a custom implementation of the C programming function printf. This project is an application of the C programming knowledge made by 2 alx students(Peter Simiyu and I).

Prototype: int _printf(const char *, ...);

Examples

String

• Input: _printf("%s\n", 'This is a string.');
• Output: This is a string.

Character

• Input: _printf("The first letter in the alphabet is %c\n", 'A');
• Output: The first letter in the alphabet is A

Integer

• Input: _printf("There are %i dozens in a gross\n", 12);
• Output: There are 12 dozens in a gross

Decimal:

• Input: _printf("%d\n", 1000);
• Output: 1000

Project Requirements

• All files will be compiled on Ubuntu 14.04 LTS
• Programs and functions will be compiled with gcc 4.8.4 using flags -Wall -Werror -Wextra and -pedantic
• Code must follow the Betty style
• Global variables are not allowed
• Authorized functions and macros:
  • write (man 2 write)
  • malloc (man 3 malloc)
  • free (man 3 free)
  • va_start (man 3 va_start)
  • va_end (man 3 va_end)
  • va_copy (man 3 va_copy)
  • va_arg (man 3 va_arg)

Mandatory Tasks

• Write function that produces output with conversion specifiers c, s, and %.
• Handle conversion specifiers d, i.
• Create a man page for your function.

Advanced Tasks

• Handle conversion specifier b.
• Handle conversion specifiers u, o, x, X.
• Use a local buffer of 1024 chars in order to call write as little as possible.
• Handle conversion specifier S.
• Handle conversion specifier p.
• Handle flag characters +, space, and # for non-custom conversion specifiers.
• Handle length modifiers l and h for non-custom conversion specifiers.
• Handle the field width for non-custom conversion specifiers.
• Handle the precision for non-custom conversion specifiers.
• Handle the 0 flag character for non-custom conversion specifiers.
• Handle the custom conversion specifier r that prints the reversed string.
• Handle the custom conversion specifier R that prints the rot13'ed string.
• All above options should work well together.

File Descriptions

• _printf.c: - contains the fucntion _printf, which uses the prototype int _printf(const char *format, ...);. The format string is composed of zero or more directives. See man 3 printf for more detail. _printf will return the number of characters printed (excluding the null byte used to end output to strings) and will write output to stdout, the standard output stream.
• _putchar.c: - contains the function _putchar, which writes a character to stdout.
• holberton.h: - contains all function prototypes used for _printf.
• man_3_printf: - manual page for the custom _printf function.
• print_chars.c: - contains the functions print_c, print_s, print_S, and print_r which handle the conversion specifiers c, s, S, and r, respectively, as well as hex_print, which prints a char's ascii value in uppercase hex
• print_numbers.c: - contains the functions print_i and print_d, which handle the conversion specifiers i and d, respectively
• print_hex.c: - contains the functions print_hex, which prints an unsigned int in hexidecimal form, print_x, print_X, and print_p, which handle the conversion specifiers x, X, and p, respectively
• print_unsigned_int.c: - contains the functions print_u, print_o, and print_b, which handle the conversion specifiers u, o, and b, respectively
• print_rot13.c - contains the function print_R, which handles the conversion specifier R

Authors

David Oluwafemi | @oluw4femi Peter Simiyu