std:: basic_ios
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Defined in header
<ios>
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template
<
class
CharT,
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The class
std::basic_ios
provides facilities for interfacing with objects that have
std::basic_streambuf
interface. Several
std::basic_ios
objects can refer to one actual
std::basic_streambuf
object.
Inheritance diagram
Several typedefs for common character types are provided:
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Defined in header
<ios>
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| Type | Definition |
std::ios
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std :: basic_ios < char > |
std::wios
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std :: basic_ios < wchar_t > |
Member types
| Member type | Definition |
char_type
|
CharT
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traits_type
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Traits
; the program is ill-formed if
Traits::char_type
is not
CharT
.
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int_type
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Traits::int_type
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pos_type
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Traits::pos_type
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off_type
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Traits::off_type
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Public member functions
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constructs the object
(public member function) |
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[virtual]
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destructs the object
(virtual public member function) |
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operator=
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the copy assignment operator is deleted
(public member function) |
State functions |
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checks if no error has occurred i.e. I/O operations are available
(public member function) |
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checks if end-of-file has been reached
(public member function) |
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checks if an error has occurred
(public member function) |
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checks if a non-recoverable error has occurred
(public member function) |
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checks if an error has occurred (synonym of
fail()
)
(public member function) |
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checks if no error has occurred (synonym of
!
fail()
)
(public member function) |
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returns state flags
(public member function) |
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sets state flags
(public member function) |
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modifies state flags
(public member function) |
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Formatting |
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copies formatting information
(public member function) |
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manages the fill character
(public member function) |
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Miscellaneous |
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manages exception mask
(public member function) |
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sets the locale
(public member function) |
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manages associated stream buffer
(public member function) |
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manages tied stream
(public member function) |
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narrows characters
(public member function) |
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widens characters
(public member function) |
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Protected member functions
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initializes a default-constructed
std::basic_ios
(protected member function) |
|
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(C++11)
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moves from another
std::basic_ios
except for
rdbuf
(protected member function) |
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(C++11)
|
swaps with another
std::basic_ios
except for
rdbuf
(protected member function) |
replaces the
rdbuf
without clearing its error state
(protected member function) |
Inherited from std:: ios_base
Member functions
Formatting |
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manages format flags
(public member function of
std::ios_base
)
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sets specific format flag
(public member function of
std::ios_base
)
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clears specific format flag
(public member function of
std::ios_base
)
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manages decimal precision of floating point operations
(public member function of
std::ios_base
)
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manages field width
(public member function of
std::ios_base
)
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Locales |
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sets locale
(public member function of
std::ios_base
)
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returns current locale
(public member function of
std::ios_base
)
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Internal extensible array |
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[static]
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returns a program-wide unique integer that is safe to use as index to
pword()
and
iword()
(public static member function of
std::ios_base
)
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resizes the private storage if necessary and access to the
long
element at the given index
(public member function of
std::ios_base
)
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resizes the private storage if necessary and access to the
void
*
element at the given index
(public member function of
std::ios_base
)
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Miscellaneous |
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registers event callback function
(public member function of
std::ios_base
)
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[static]
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sets whether C++ and C I/O libraries are interoperable
(public static member function of
std::ios_base
)
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Member classes |
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stream exception
(public member class of
std::ios_base
)
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initializes standard stream objects
(public member class of
std::ios_base
)
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Member types and constants |
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| Type | Explanation | ||||||||||||||||||||||||||||||||||||||
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stream open mode type
The following constants are also defined:
(typedef) |
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formatting flags type
The following constants are also defined:
(typedef) |
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state of the stream type
The following constants are also defined:
(typedef) |
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seeking direction type
The following constants are also defined:
(typedef) |
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specifies event type
(enum) |
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callback function type
(typedef) |
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Notes
Straightforward implementation of
std::basic_ios
stores only the following members (which all depend on the template parameters and thus cannot be part of
std::ios_base
):
-
the fill character (see
fill()) -
the tied stream pointer (see
tie()) -
the associated stream buffer pointer (see
rdbuf()).
Actual implementations vary:
Microsoft Visual Studio stores just those three members.
LLVM libc++ stores 1 less member: it maintains the
rdbuf
pointer as a
void
*
member of
ios_base
.
GNU libstdc++ stores 4 additional members: three cached facets and a flag to indicate that fill was initialized.