Hi all,
I want to use a single std::stringbuf for writing (by a std::ostream)
and for reading (by a std::istream), concurrently in two threads.
This came to my mind, because the code for reading should be as with any other istream and cannot be changed.
Now my problem is, that a do not get any data in the reading loop
std::ofstream tempfile("test. pdf",
std::ios_base:: out | std::ios_base:: trunc | std::ios_base:: binary);
while (!is->eof()) {
is->read(buffer, bufferSize);
tempfile.write( buffer, is->gcount());
tempfile.flush;
}
The writing thread proceeds as expected and finally finishes writing.
Any hints? What are my misconceptions?
Thanks,
Christoph
3 2299
How did you define 'is'?
is is an istream* managed by a boost::shared_p tr - typedef boost::shared_ptr<std::istream> IStreamP;
-
IStreamP is = data->getIStream();
The istream is created with the same std::stringbuf used during writing (in a ostream of course!).
It seems that I do not get any content during reading or the read pointer is always at the end or ..
Hi again,
let me put it differently. I just tested, that it does not depend on
multi-threading.
If I write to the stringbuf in a std:: ostream (or a std::iostream) and
then try to read
with a std::istream* is (or the same std::iostream* is), it does not
work either.
I immediatly get, (is->fail() == true) :-(
Also tried is->seekg(0); with the same result.
Does anybody have an example showing usage of stringbuf with
std:: ostream and std::istream?
Or can somebody give some details on the internals, when
(is->fail()==true ) and (is->eof()==true) does occur?
Thanks very much,
Christoph
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