Why you use scanf?

Answer 1

scanf is a function that reads data with specified format from a given string stream source, originated from C Programming language, and is present in many other programming languages.

The scanf function prototype is:

int scanf(const char *format, ...);

The function returns the total number of items successfully matched, which can be less than the number requested. If the input stream is exhausted or reading from it otherwise fails before any items are matched, EOF is returned.

So far as is traceable, "scanf" stands for "scan format", because it scans the input for valid tokens and parses them according to a specified format.

Usage

The scanf function is found in C, in which it reads input for numbers and other datatypes from standard input (often a command line interface or similar kind of a text user interface).

The following shows code in C that reads a variable number of unformatted decimal integers from the console and prints out each of them on a separate line:

#include

int

main(void)

{

int n;

while (scanf("%d", &n) 1)

puts(word);

return 0;

}

No matter what the datatype the programmer wants the program to read, the arguments (such as &nabove) must be pointers pointing to memory. Otherwise, the function will not perform correctly because it will be attempting to overwrite the wrong sections of memory, rather than pointing to the memory location of the variable you are attempting to get input for.

As scanf is designated to read only from standard input, many programming languages with interfaces, such as PHP, have derivatives such as sscanfand fscanf but not scanf itself.