The first function ever to be used in C printf() from the standard input/output library,
I have decided to created my own ft_printf() library as I was very curious how it works
and I wanted to get a better understanding of the variadic function concept and how to use its macros.
I have implemented all of these specifiers cspdiuxX% in addition to any combination
of these flags -0.#+space and width in my function.
Note: I wasn't allowd to use
swtichand only the use the bellow external functions as a challenge.
| Program name | libftprintf.a |
|---|---|
| External functs | malloc, free, write, va_start, va_arg, va_copy, va_end |
| Libft | My own library |
| Description | A library that contains ft_printf(), a function that will mimic the original printf() |
• %c Prints a single character.
• %s Prints a string (as defined by the common C convention).
• %p The void * pointer argument has to be printed in hexadecimal format.
• %d Prints a decimal (base 10) number.
• %i Prints an integer in base 10.
• %u Prints an unsigned decimal (base 10) number.
• %x Prints a number in hexadecimal (base 16) lowercase format.
• %X Prints a number in hexadecimal (base 16) uppercase format.
• %% Prints a percent sign.
| Flags | Description |
|---|---|
| - | Left-justify within the given field width; Right justification is the default (see width sub-specifier). |
| + | Forces to preceed the result with a plus or minus sign (+ or -) even for positive numbers. By default, only negative numbers are preceded with a - sign. |
| (space) | If no sign is going to be written, a blank space is inserted before the value. |
| # | Used with x or X specifiers the value is preceeded with 0, 0x or 0X respectively for values different than zero. |
| 0 | Left-pads the number with zeroes (0) instead of spaces when padding is specified (see width sub-specifier). |
| Width | Description |
|---|---|
| (number) | Minimum number of characters to be printed. If the value to be printed is shorter than this number, the result is padded with blank spaces. The value is not truncated even if the result is larger. |
| * | The width is not specified in the format string, but as an additional integer value argument preceding the argument that has to be formatted. |
| Precision | Description |
|---|---|
| .number | For integer specifiers (d, i, u, x, X): precision specifies the minimum number of digits to be written. If the value to be written is shorter than this number, the result is padded with leading zeros. The value is not truncated even if the result is longer. A precision of 0 means that no character is written for the value 0. For s: this is the maximum number of characters to be printed. By default all characters are printed until the ending null character is encountered. If the period is specified without an explicit value for precision, 0 is assumed. |
| .* | The precision is not specified in the format string, but as an additional integer value argument preceding the argument that has to be formatted. |
Clone the repository in the desired directory.
git clone https://github.com/SolarisCode/ft_printf.gitThen use make inside the pervious directory either with all or bonus rule if you want to use the flags.
make allor
make bounsThe pervious command will result in the static library file libftprintf.a and you can include it
with the header file ft_printf.h or ft_printf_bonus.h if you make with bonus
while you complie your own programs like below:
gcc main.c -L"the directory that has the library" -I"the directory that has the include file" -lprintfFeel free to contact me if you have a better way to implement any of the specifiers or the flags :)