std::basic_istream<CharT,Traits>::gcount

 

C++

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std::basic_istream

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cinwcin

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basic_istream::gcount

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operator>>(std::basic_istream)

 

std::streamsize gcount() const;

Returns the number of characters extracted by the last unformatted input operation.

The following member functions of basic_istream change the value of subsequent gcount() calls:

• move constructor
• swap()
• get()
• getline()
• ignore()
• read()
• readsome()
• operator>>(basic_streambuf*)

The following functions set gcount() to zero:

• constructor
• putback()
• unget()
• peek()

Parameters

(none)

Return value

The number of characters extracted by the last unformatted input operation

Example

Run this code

#include <iostream>
#include <sstream>
 
int main()
{
    char x[20];
    std::istringstream stream("Hello World");
 
    stream.read(x, sizeof x);
    std::cout << "Characters extracted: " << stream.gcount();
}

Output:

Characters extracted: 11