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basic_istream::_Readsome_s

Read from buffer only.

streamsize _Readsome_s(
    char_type *_Str,
    size_t _Str_size,
    streamsize _Count
);

Parameters

  • _Str
    The array in which to read the characters.

  • _Str_size
    The size of _Str.

  • _Count
    The number of characters to read.

Return Value

The count of items in the buffer.

Remarks

The unformatted input function extracts up to count elements and stores them in the array beginning at _Str. If good is false, the function calls setstate(failbit). Otherwise, it assigns the value of rdbuf->in_avail to N. If N < 0, the function calls setstate(eofbit). Otherwise, it replaces the value stored in N with the smaller of _Count and N, and then calls read(_Str, N). In any case, the function returns gcount.

Example

// basic_istream__Readsome_s.cpp
// compile with: /EHsc
#include <iostream>
using namespace std;

int main( )
{
    const int c_size = 10;
    char c[c_size];
    int count = 5;

    cout << "Type 'abcdefgh': ";

    // Can read from buffer or console
    cin._Read_s(&c[0], c_size, 2);

    // Can only read from buffer, not from console
    cin._Readsome_s(&c[0], c_size, count);
    c[count] = 0;
    cout << c << endl;
}

Input

abcdefgh

Sample Output

Type 'abcdefgh': abcdefgh
cdefg

Requirements

Header: <istream>

Namespace: std

See Also

Reference

basic_istream Class

iostream Programming

iostreams Conventions

Safe Libraries: Standard C++ Library

Other Resources

basic_istream Members