Standard C++ LibraryCopyright 1996, Rogue Wave Software, Inc.

NAME

  istrstream

SYNOPSIS

  #include <strstream>
  class istrstream
  : public basic_istream<char>

DESCRIPTION

  The class istrstream provides functionality to read characters from an
  array in memory. It uses a private strstreambuf object to control the
  associated array object. It inherits from basic_istream<char> and therefore
  can use all the formatted and unformatted input functions.

INTERFACE

  class istrstream : public basic_istream<char> {

  public:

   typedef char_traits<char>             traits;

   typedef char                         char_type;
   typedef typename traits::int_type    int_type;
   typedef typename traits::pos_type    pos_type;
   typedef typename traits::off_type    off_type;

   explicit istrstream(const char *s);
   istrstream(const char *s, streamsize n);
   explicit istrstream(char *s);
   istrstream(char *s, streamsize n);

   virtual ~istrstream();

   strstreambuf *rdbuf() const;

   char *str();

  };

TYPES

  char_type
     The type char_type is a synonym of type char.

  int_type
     The type int_type is a synonym of type traits::in_type.

  off_type
     The type off_type is a synonym of type traits::off_type.

  pos_type
     The type pos_type is a synonym of type traits::pos_type.

  traits
     The type traits is a synonym of type char_traits<char>.

CONSTRUCTORS

  explicit istrstream(const char* s);
  explicit istrstream(char* s);
     Constructs an object of class istrstream, initializing the base class
     basic_istream<char> with the associated strstreambuf object. The
     strstreambuf object is initialized by calling strstreambuf(s,0), where s
     shall designate the first element of an NTBS.

  explicit istrstream(const char* s, streamsize n);
  explicit istrstream(char* s, streamsize n);
     Constructs an object of class istrstream, initializing the base class
     basic_istream<char> with the associated strstreambuf object. The
     strstreambuf object is initialized by calling strstreambuf(s,n), where s
     shall designate the first element of an array whose length is n
     elements, and n shall be greater than zero.

DESTRUCTORS

  virtual ~istrstream();
     Destroys an object of class istrstream.

MEMBER FUNCTIONS

  char*
  str();
     Returns a pointer to the underlying array object which may be null.

  strstreambuf*
  rdbuf() const;
     Returns a pointer to the private strstreambuf object associated with the
     stream.

EXAMPLES

  //
  // stdlib/examples/manual/istrstream.cpp
  //
  #include<iostream>
  #include<strstream>

  void main ( )
  {
   using namespace std;

   const char* p="C'est pas l'homme qui prend la mer, ";
   char* s="c'est la mer qui prend l'homme";

    // create an istrstream object and initialize
    // the underlying strstreambuf with p
   istrstream in_first(p);

    // create an istrstream object and initialize
    // the underlying strstreambuf with s
   istrstream in_next(s);

    // create an ostrstream object
   ostrstream out;

    // output the content of in_first and
    // in_next to out
   out << in_first.rdbuf() << in_next.str();

    // output the content of out to stdout
   cout << endl << out.rdbuf() << endl;

    // output the content of in_first to stdout
   cout << endl << in_first.str();

    // output the content of in_next to stdout
   cout << endl << in_next.rdbuf() << endl;

  }

SEE ALSO

  char_traits(3C++std), ios_base(3C++std), basic_ios(3C++std),
  strstreambuf(3C++std), ostrstream(3C++std), strstream(3c++)

  Working Paper for Draft Proposed International Standard for Information
  Systems--Programming Language C++, Annex D Compatibility features Section
  D.6.2

STANDARDS CONFORMANCE

  ANSI X3J16/ISO WG21 Joint C++ Committee



privacy and legal statement