std::ios_base

From Cppreference

C++ Standard Library
Language Utilities library Strings library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11)
Input/output library
basic_streambuf basic_filebuf basic_stringbuf ios_base basic_ios basic_istream basic_ostream basic_iostream basic_ifstream basic_ofstream basic_fstream basic_istringstream basic_ostringstream basic_stringstream I/O manipulators C-style I/O
std::ios_base
Member functions ios_base::ios_base ios_base::~ios_base Formatting ios_base::flags ios_base::setf ios_base::unsetf ios_base::precision ios_base::width Locales ios_base::imbue ios_base::getloc Internal extensible array ios_base::xalloc ios_base::iword ios_base::pword Miscellaneous ios_base::register_callback ios_base::sync_with_stdio Member classes ios_base::failure ios_base::Init Member types ios_base::openmode ios_base::fmtflags ios_base::iostate ios_base::seekdir ios_base::event ios_base::event_callback

Defined in header <ios>
class ios_base;

The class ios_base provides facilities for inspecting error state of the stream object. Character type independent formatting flags are stored here as well.

Contents 1 Member functions 1.1 Formatting 1.2 Locales 1.3 Internal extensible array 1.4 Miscellaneous 2 Member classes 3 Member types and constants

[edit] Member functions

(constructor)	constructs the object (public member function)
(destructor)	destructs the object (public member function)
Formatting
flags	manages format flags (public member function)
setf	sets specific format flag (public member function)
unsetf	clears specific format flag (public member function)
precision	manages decimal precision of floating point operations (public member function)
width	manages field width (public member function)
Locales
imbue	sets locale (public member function)
getloc	returns current locale (public member function)
Internal extensible array
xalloc [static]	returns an unique index to be used to access elements in the internal extensible array (public static member function)
iword	accesses specified element in the internal extensible array of long elements (public member function)
pword	accesses specified element in the internal extensible array of void* elements (public member function)
Miscellaneous
register_callback	registers event callback function (public member function)
sync_with_stdio [static]	sets whether C++ and C IO libraries are interoperable (public static member function)
Member classes
failure	stream exception (public member class)
Init	initializes standard stream objects (public member class)

Member types and constants
Type	Explanation
openmode	stream open mode type The following constants are also 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
fmtflags	formatting flags type The following constants are also defined: Constant Explanation dec uses decimal base for conversions oct use octal base for conversions hex use hexadecimal base for conversions basefield dec|oct|hex. Useful for masking operations left left adjustment (adds fill characters to the right) right right adjustment (adds fill characters to the left) internal internal adjustment (adds fill characters to the internal designated point) adjustfield left|right|internal. Useful for masking operations scientific generate floating point types using scientific notation fixed generate floating point types using fixed notation floatfield scientific|fixed. Useful for masking operations boolalpha insert and extract bool type in alphanumeric format showbase generate a prefix indicating the numeric base for integer number output showpoint generate a decimal-point character unconditionally for floating-point number output showpos generate a + character for non-negative numeric output skipws skip leading whitespace before certain input operations unitbuf flush the output after each output operation uppercase replace certain lowercase letters with their uppercase equivalents in certain output output operations
iostate	state of the stream type The following constants are also defined: Constant Explanation goodbit no error badbit irrecoverable stream error failbit input/output operation failed (formatting or extraction error) eofbit associated input sequence has reached end-of-file
seekdir	seeking direction type The following constants are also defined: Constant Explanation beg the beginning of a stream end the ending of a stream cur the current position of stream position indicator
event	specifies event type
event_callback	callback function type