std::basic_spanbuf<CharT,Traits>::basic_spanbuf
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< cpp | io | basic spanbuf
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std::basic_spanbuf
Public member functions
basic_spanbuf::basic_spanbuf
(C++23)
(C++23)
(C++23)
(C++23)
Protected member functions
(C++23)
(C++23)
(C++23)
Non-member functions
(C++23)
basic_spanbuf() : basic_spanbuf(std::ios_base::in | std::ios_base::out ) {}
(1)
(since C++23)
explicit basic_spanbuf( std::ios_base::openmode which )
: basic_spanbuf(std::span <CharT>{}, which) {}
(2)
(since C++23)
: basic_spanbuf(std::span <CharT>{}, which) {}
explicit basic_spanbuf( std::span <CharT> buf, std::ios_base::openmode which =
std::ios_base::in | std::ios_base::out );
(3)
(since C++23)
std::ios_base::in | std::ios_base::out );
basic_spanbuf( const basic_spanbuf& ) = delete;
(4)
(since C++23)
basic_spanbuf( basic_spanbuf&& rhs );
(5)
(since C++23)
1) Default constructor. Creates a
basic_spanbuf that has no underlying buffer and is opened for both input and output. The pointers to get and put area are set to the null pointer value.2) Same as (1), except that the
basic_spanbuf is opened in mode specified by which.3) Creates a
basic_spanbuf that manages the underlying buffer referenced by buf (or has no underlying buffer if buf is empty) and is opened in mode specified by which. The pointers to get and put area are set as following, or to the null pointer value if not mentioned in the table:
| Set bits in open mode (affecting pointers to get area) |
Return value after setting | ||
|---|---|---|---|
| eback() | gptr() | egptr() | |
| std::ios_base::in | s.data() | s.data() | s.data() + s.size() |
| Set bits in open mode (affecting pointers to put area) |
Return value after setting | ||
| pbase() | pptr() | epptr() | |
| std::ios_base::out && !std::ios_base::ate | s.data() | s.data() | s.data() + s.size() |
| std::ios_base::out && std::ios_base::ate | s.data() | s.data() + s.size() | s.data() + s.size() |
4) Copy constructor is deleted.
basic_spanbuf is not copyable.5) Move constructor. Move-constructs the std::basic_streambuf base subobject from that of rhs. The pointers to get and put area, the open mode, and the underlying buffer (if any) are identical to those in rhs before construction.
It is implementation-defined whether rhs still holds the underlying buffer after the move-construction.
It is implementation-defined whether rhs still holds the underlying buffer after the move-construction.
Contents
[edit] Parameters
buf
-
a std::span referencing the underlying buffer
rhs
-
another
basic_spanbuf
which
-
specifies stream open mode. It is bitmask type, the following constants are defined:
Constant
Explanation
app
seek to the end of stream before each write
binary
open in binary mode
in
open for reading
out
open for writing
trunc
discard the contents of the stream when opening
ate
seek to the end of stream immediately after open
noreplace (C++23)
open in exclusive mode
[edit] Notes
These constructors are typically called by the constructors of std::basic_ispanstream, std::basic_ospanstream, and std::basic_spanstream.
[edit] Example
This section is incomplete
Reason: no example
Reason: no example
[edit] See also
constructs the
(public member function of
basic_ispanstream (public member function of
std::basic_ispanstream<CharT,Traits>) [edit]
constructs the
(public member function of
basic_ospanstream (public member function of
std::basic_ospanstream<CharT,Traits>) [edit]
constructs the
(public member function of
basic_spanstream (public member function of
std::basic_spanstream<CharT,Traits>) [edit]