std::basic_syncbuf<CharT,Traits,Allocator>::emit

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Input/output library

I/O manipulators
Print functions(C++23)
C-style I/O
Buffers
basic_streambuf
basic_filebuf
basic_stringbuf
basic_spanbuf (C++23)
strstreambuf (C++98/26*)
basic_syncbuf (C++20)
Streams
Abstractions
ios_base
basic_ios
basic_istream
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basic_ifstream
basic_ofstream
basic_fstream
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basic_istringstream
basic_ostringstream
basic_stringstream
Array I/O
basic_ispanstream (C++23)
basic_ospanstream (C++23)
basic_spanstream (C++23)
istrstream (C++98/26*)
ostrstream (C++98/26*)
strstream (C++98/26*)
Synchronized Output
basic_osyncstream (C++20)
Types
streamoff
streamsize
fpos
Error category interface
iostream_category (C++11)
io_errc (C++11)

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std::basic_syncbuf

Public member functions
basic_syncbuf::basic_syncbuf (C++20)
basic_syncbuf::operator= (C++20)
basic_syncbuf::~basic_syncbuf (C++20)
basic_syncbuf::swap (C++20)
basic_syncbuf::emit (C++20)
basic_syncbuf::get_wrapped (C++20)
basic_syncbuf::get_allocator (C++20)
basic_syncbuf::set_emit_on_sync (C++20)
Protected member functions
basic_syncbuf::sync (C++20)
Non-member functions
swap(std::basic_syncbuf) (C++20)

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bool emit();

Atomically transmits all pending output to the wrapped stream.

Allemit() calls transferring characters to the same wrapped stream buffer object appear to execute in a total order, where eachemit() callsynchronizes-with subsequentemit() calls in that total order, even if these calls are made through difference instances ofstd::basic_syncbuf/std::basic_osyncstream. In practice, this means that emit() takes a lock uniquely associated with the wrapped stream object: for example, it could be held in a static hash map where the address of the wrapped stream is used as the key.

If a call had been made tosync since the last call toemit(), then also flushes the wrapped stream by callingpubsync() on it.

[edit]Parameters

(none)

[edit]Return value

true if all of the following is true:

there is a wrapped stream (the wrapped streambuf pointer is not null)
all characters from the temporary storage were successfully sent into the wrapped stream
the call topubsync(), if requested, also completed successfully.

Returnsfalse otherwise.

[edit]Notes

Normally called by the destructor or move assignment of the owningstd::basic_osyncstream, or bystd::basic_osyncstream::emit.

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

(destructor)	destroys the`basic_osyncstream` and emits its internal buffer (public member function of`std::basic_osyncstream<CharT,Traits,Allocator>`)[edit]
emit	calls`emit()` on the underlying`basic_syncbuf` to transmit its internal data to the final destination (public member function of`std::basic_osyncstream<CharT,Traits,Allocator>`)[edit]
(constructor)	constructs a`basic_syncbuf` object (public member function)[edit]