Annex D (normative) Compatibility features [depr]

D.6 char* streams [depr.str.strstreams]

D.6.3 Class ostrstream [depr.ostrstream]

namespace std {
  class ostrstream : public basic_ostream<char> {
  public:
    ostrstream();
    ostrstream(char* s, int n, ios_base::openmode mode = ios_base::out);
    virtual ~ostrstream();

    strstreambuf* rdbuf() const;
    void freeze(bool freezefl = true);
    char* str();
    int pcount() const;
  private:
    strstreambuf sb;  // exposition only
  };
}
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The class ostrstream supports the writing of objects of class strstreambuf. It supplies a strstreambuf object to control the associated array object. For the sake of exposition, the maintained data is presented here as:

D.6.3.1 ostrstream constructors [depr.ostrstream.cons]

ostrstream();

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Effects: Constructs an object of class ostrstream, initializing the base class with ostream(&sb) and initializing sb with strstreambuf().

ostrstream(char* s, int n, ios_base::openmode mode = ios_base::out);

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Effects: Constructs an object of class ostrstream, initializing the base class with ostream(&sb), and initializing sb with one of two constructors:

  • (2.1)

    If (mode & app) == 0, then s shall designate the first element of an array of n elements.

    The constructor is strstreambuf(s, n, s).

  • (2.2)

    If (mode & app) != 0, then s shall designate the first element of an array of n elements that contains an ntbs whose first element is designated by s. The constructor is strstreambuf(s, n, s + std​::​strlen(s)).333

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The function signature strlen(const char*) is declared in <cstring>.

D.6.3.2 Member functions [depr.ostrstream.members]

strstreambuf* rdbuf() const;

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Returns: (strstreambuf*)&sb.

void freeze(bool freezefl = true);

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Effects: Calls rdbuf()->freeze(freezefl).

char* str();

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Returns: rdbuf()->str().

int pcount() const;

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Returns: rdbuf()->pcount().