Standard C++ Library
Copyright 1998, Rogue Wave Software, Inc.
NAME
istrstream
- Reads characters from an array in memory.
SYNOPSIS
#include <strstream>
class istrstream
: public basic_istream<char>
DESCRIPTION
The class istrstream reads 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.
This is a deprecated feature and might not be available in
future versions.
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 initial-
ized by calling strstreambuf(s,0), where s designates the
first element of an NTBS (null terminated byte string).
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 initial-
ized by calling strstreambuf(s,n), where s designates the
first element of an array whose length is n elements and
n is greater than zero.
DESTRUCTORS
virtual ~istrstream();
Destroys an object of class istrstream.
MEMBER FUNCTIONS
char*
str();
Returns a pointer to the underlying array object that may
be null.
strstreambuf*
rdbuf() const;
Returns a pointer to the private strstreambuf object
associated with the stream.
EXAMPLE
//
// 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, ";
const 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++), ios_base(3C++), basic_ios(3C++),
strstreambuf(3C++), ostrstream(3C++), strstream(3c++)
Working Paper for Draft Proposed International Standard for
Information Systems--Programming Language C++, Annex D Com-
patibility features Section D.6.2
STANDARDS CONFORMANCE
ANSI X3J16/ISO WG21 Joint C++ Committee