std::strstreambuf::pcount

 

C++

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C-style I/O

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basic_streambuf

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std::strstreambuf

Public member functions

strstreambuf::strstreambuf

strstreambuf::~strstreambuf

strstreambuf::freeze

strstreambuf::str

strstreambuf::pcount

Protected member functions

strstreambuf::underflow

strstreambuf::pbackfail

strstreambuf::overflow

strstreambuf::setbuf

strstreambuf::seekoff

strstreambuf::seekpos

 

int pcount() const;		(deprecated in C++98) (removed in C++26)

Returns the number of characters written to the output sequence.

If the next pointer for the put area (std::streambuf::pptr()) is a null pointer, returns zero.

Otherwise, returns the next pointer in the put area minus the beginning pointer in the put area, that is pptr() - pbase().

Parameters

(none)

Return value

The number of characters written to the put area.

Example

Run this code

#include <iostream>
#include <strstream>
 
int main()
{
    std::strstream dyn; // dynamically-allocated output buffer
    dyn << "Test: " << 1.23 << std::ends;
    std::strstreambuf* buf = dyn.rdbuf();
    std::cout << "The size of the output is "
              << buf->pcount() // or just buf.pcount()
              << " and it holds \"" << dyn.str() << "\"\n";
    dyn.freeze(false); // after calling .str() on a dynamic strstream
 
    char arr[10];
    std::ostrstream user(arr, 10); // user-provided output buffer
    buf = user.rdbuf();
    user << 1.23; // note: no std::ends
    std::cout.write(arr, buf->pcount()); // or just user.pcount()
    std::cout << '\n';
 
    std::istrstream lit("1 2 3"); // read-only fixed-size buffer
    buf = lit.rdbuf();
    // istrstream has no member pcount(), so lit.pcount() won't work
    std::cout << "Input-only pcount() = " << buf->pcount() << '\n';
}

Output:

The size of the output is 11 and it holds "Test: 1.23"
1.23
Input-only pcount() = 0

See also

pcount	obtains the number of characters written (public member function of std::strstream)
pcount	obtains the number of characters written (public member function of std::ostrstream)