std::ostrstream::pcount

C++

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Technical Specifications

Input/output library

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basic_streambuf

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basic_osyncstream (C++20)

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iostream_category (C++11)

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std::ostrstream

Member functions

ostrstream::ostrstream

ostrstream::~ostrstream

ostrstream::rdbuf

ostrstream::str

ostrstream::freeze

ostrstream::pcount

int pcount() const;

Returns the number of characters that were output in the put area of the associated std::strstreambuf. Effectively calls rdbuf()->pcount()

Parameters

(none)

Return value

The number of characters in the put area, or zero if nothing was output.

Example

Run this code

#include <strstream>
#include <iostream>

int main()
{
    std::ostrstream dyn; // dynamically-allocated output buffer
    dyn << "Test: " << 1.23 << std::ends;
    std::cout << "The size of the output is " << dyn.pcount()
              << " and it holds \"" << dyn.str() << "\"\n";
    dyn.freeze(false);

    char buf[10];
    std::ostrstream user(buf, 10); // user-provided output buffer
    user << 1.23; // note: no std::ends
    std::cout.write(buf, user.pcount());
    std::cout << '\n';
}

Output:

The size of the output is 11 and it holds "Test: 1.23"
1.23

See also

pcount

returns the next pointer minus the beginning pointer in the output sequence: the number of characters written (public member function of std::strstreambuf)