Function Details : vprintf

intvprintf(const char * format,va_list args) ;

Return Type : int

Integer type (typically 4 bytes, -2,147,483,648 to 2,147,483,647)

Read about return values of vprintf function .

1st Parameter Type : const char *

Pointer to read-only string

1st Parameter

Pointer to a null-terminated string specifying the format of the output. It may include format specifiers like `%d`, `%s`, etc.

2nd Parameter Type : va_list

A data type used to hold information about variable arguments passed to a variadic function. It is initialized with `va_start`, used with `va_arg`, and cleaned up with `va_end`.

2nd Parameter

The variable argument list containing the values to be formatted and written. It must be initialized with `va_start`.

Read more about parameters of vprintf in parameters section

The vprintffunction in C language Prints formatted output to the standard output using a va_list.

vprintf is similar to printf, but instead of taking a variable number of arguments, it takes a va_list that has been initialized by va_start. This function is useful for implementing custom variadic functions that need to forward their arguments to printf for output.

The vprintffunction takes 2 parameters:

•
const char * `format`: Pointer to a null-terminated string specifying the format of the output. It may include format specifiers like `%d`, `%s`, etc.
•
va_list `args`: The variable argument list containing the values to be formatted and written. It must be initialized with `va_start`.

Writes a formatted output to the standard output (`stdout`) based on the format string `format` and the values in the `va_list` object `args`. Returns the number of characters written, or a negative value if an error occurs.

The vprintf function return value :

Returns the number of characters written, or a negative value if an error occurred

Output

This example demonstrates using vprintf in a custom logging function that can handle various types of arguments.