std::istrstream::istrstream (3) - Linux Manuals

std::istrstream::istrstream: std::istrstream::istrstream

NAME

std::istrstream::istrstream - std::istrstream::istrstream

Synopsis

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

// Run this code

  #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