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std::istrstream::istrstream

explicit istrstream(const char* s);
 (1) 
explicit istrstream(char* s);
 (2) 
istrstream(const char* s, std::streamsize n);
 (3) 
istrstream(char* s, std::streamsize n);
 (4)

Constructs new istrstream and its underlying std::strstreambuf.

1,2) Constructs the underlying std::strstreambuf by calling strstreambuf(s,0) and initializes the base class with the address of the strstreambuf. The behavior is undefined if s is not pointing at an element of a null-terminated array.
3,4) Constructs the underlying std::strstreambuf by calling strstreambuf(s,n) and initializes the base class with the address of the strstreambuf. The behavior is undefined if s is not pointing at an element of an array whose length is at least n elements.

Parameters

s - C-string or char array to use as the contents of the stream
n - size of the array

Example

#include <iostream>
#include <strstream>
 
int main()
{
    std::istrstream s1("1 2 3"); // string literal
    int n1,n2,n3;
    if(s1 >> n1 >> n2 >> n3)
        std::cout << n1 << ", " << n2 << ", " << n3 << '\n';
 
    char arr[] = {'4', ' ', '5', ' ', '6'};
    std::istrstream s2(arr, sizeof arr);
    if(s2 >> n1 >> n2 >> n3)
        std::cout << n1 << ", " << n2 << ", " << n3 << '\n';
}

Output:

1, 2, 3
4, 5, 6

See also

constructs a strstreambuf object
(public member function of std::strstreambuf)
constructs an strstream, optionally allocating the buffer
(public member function of std::ostrstream)
constructs an strstream, optionally allocating the buffer
(public member function of std::strstream)

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