printf format specifier

general

%[flags][width][.precision][length]specifier

flag

Flag	Description
`-`	Left-justify: The result is left-aligned within the specified field width. By default, it is right-aligned.
`+`	Sign: The result of a signed conversion will always begin with a sign (`+` or `-`). By default, only negative values have a sign.
(space)	Space: If the first character of a signed conversion is not a sign, a space is prepended. This is ignored if the `+` flag is present.
`#`	Alternate Form: For `o`, the output is prefixed with `0`. For `x` and `X`, it's prefixed with `0x` and `0X` respectively. For `a`, `A`, `e`, `E`, `f`, `F`, `g`, and `G`, the output will always contain a decimal point.
`0`	Zero-padding: For numeric types, the output is padded with leading zeros instead of spaces to fill the field width. This is ignored if the `-` flag is present.

The width sub-specifier sets the minimum number of characters to be printed.

Width	Description
`number`	A non-negative integer specifying the minimum number of characters to print. If the printed value is shorter, it is padded with spaces (or zeros if the `0` flag is used).
`*`	The width is not specified in the format string itself, but as an additional integer argument preceding the argument to be formatted.

Precision	Description
`.number`	For integer specifiers (`d`, `i`, `u`, `o`, `x`, `X`), it specifies the minimum number of digits to be written. For `e`, `E`, and `f`, it is the number of digits to appear after the decimal point. For `g` and `G`, it's the maximum number of significant digits. For `s`, it's the maximum number of characters to be printed.
`.*`	The precision is not specified in the format string itself, but as an additional integer argument preceding the argument to be formatted.

Modifier	For Integer Specifiers (`d`, `i`, `u`, `o`, `x`, `X`)	For Floating-Point Specifiers (`f`, `e`, `g`, `a`)
`h`	`short int` or `unsigned short int`	-
`hh`	`signed char` or `unsigned char`	-
`l`	`long int` or `unsigned long int`	-
`ll`	`long long int` or `unsigned long long int`	-
`L`	-	`long double`
`j`	`intmax_t` or `uintmax_t`	-
`z`	`size_t` or the corresponding signed type	-
`t`	`ptrdiff_t` or the corresponding unsigned type	-

Specifier	Data Type	Output Format
`%c`	`char`	A single character.
`%s`	`char*`	A string of characters.
`%d` or `%i`	`int`	Signed decimal integer.
`%u`	`unsigned int`	Unsigned decimal integer.
`%o`	`unsigned int`	Unsigned octal integer.
`%x`	`unsigned int`	Unsigned hexadecimal integer (lowercase letters).
`%X`	`unsigned int`	Unsigned hexadecimal integer (uppercase letters).
`%f`	`double`	Decimal floating-point number.
`%F`	`double`	Decimal floating-point number (uppercase 'INF' and 'NAN').
`%e`	`double`	Scientific notation (lowercase 'e').
`%E`	`double`	Scientific notation (uppercase 'E').
`%g`	`double`	Uses the shorter of `%f` or `%e`.
`%G`	`double`	Uses the shorter of `%F` or `%E`.
`%a`	`double`	Hexadecimal floating-point number (lowercase 'p').
`%A`	`double`	Hexadecimal floating-point number (uppercase 'P').
`%p`	`void*`	Pointer address.
`%n`	`int*`	The number of characters written so far is stored in the integer pointed to by the argument. Nothing is printed.
`%%`	None	A literal '%' character is printed.