class

std::ofstream

typedef basic_ofstream<char> ofstream;

Output file stream

ios_base
ios
ostream
ofstream

Output stream class to operate on files.

Objects of this class maintain a filebuf object as their internal stream buffer, which performs input/output operations on the file they are associated with (if any).

File streams are associated with files either on construction, or by calling member open .

This is an instantiation of basic_ofstream with the following template parameters:

template parameter	definition	comments
`charT`	`char`	Aliased as member `char_type`
`traits`	`char_traits<char>`	Aliased as member `traits_type`

Apart from the internal file stream buffer , objects of this class keep a set of internal fields inherited from ios_base , ios and istream :

field	member functions	description
Formatting	format flags	`flags` `setf` `unsetf`	A set of internal flags that affect how certain input/output operations are interpreted or generated. See member type `fmtflags` .
	field width	`width`	Width of the next formatted element to insert.
	display precision	`precision`	Decimal precision for the next floating-point value inserted.
	locale	`getloc` `imbue`	The `locale` object used by the function for formatted input/output operations affected by localization properties.
	fill character	`fill`	Character to pad a formatted field up to the field width (`width` ).
State	error state	`rdstate` `setstate` `clear`	The current error state of the stream. Individual values may be obtained by calling `good` , `eof` , `fail` and `bad` . See member type `iostate` .
State	exception mask	`exceptions`	The state flags for which a failure exception is thrown. See member type `iostate` .
Other	callback stack	`register_callback`	Stack of pointers to functions that are called when certain events occur.
	extensible arrays	`iword` `pword` `xalloc`	Internal arrays to store objects of type `long` and `void*`.
	tied stream	`tie`	Pointer to output stream that is flushed before each i/o operation on this stream.
	stream buffer	`rdbuf`	Pointer to the associated `streambuf` object, which is charge of all input/output operations.
	character count	`gcount`	Count of characters read by last unformatted input operation.

Member types

The class declares the following member types:

member type	definition
`char_type`	`char`
`traits_type`	`char_traits<char>`
`int_type`	`int`
`pos_type`	`streampos`
`off_type`	`streamoff`

These member types are inherited from its base classes ostream and ios_base :

event: Type to indicate event type (public member type)

event_callback: Event callback function type (public member type)

failure: Base class for stream exceptions (public member class)

fmtflags: Type for stream format flags (public member type)

Init: Initialize standard stream objects (public member class)

iostate: Type for stream state flags (public member type)

openmode: Type for stream opening mode flags (public member type)

seekdir: Type for stream seeking direction flag (public member type)

sentry: Prepare stream for output (public member class)

Public member functions

(constructor): Construct object (public member function)

open: Open file (public member function)

is_open: Check if file is open (public member function)

close: Close file (public member function)

rdbuf: Get stream buffer (public member function)

operator=: Move assignment (public member function)

swap: Swap internals (public member function)

Public member functions inherited from `ostream`

operator<<: Insert formatted output (public member function)

put: Put character (public member function)

write: Write block of data (public member function)

tellp: Get position in output sequence (public member function)

seekp: Set position in output sequence (public member function)

flush: Flush output stream buffer (public member function)

Public member functions inherited from `ios`

good: Check whether state of stream is good (public member function)

eof: Check whether eofbit is set (public member function)

fail: Check whether either failbit or badbit is set (public member function)

bad: Check whether badbit is set (public member function)

operator!: Evaluate stream (not) (public member function)

operator bool: Evaluate stream (public member function)

rdstate: Get error state flags (public member function)

setstate: Set error state flag (public member function)

clear: Set error state flags (public member function)

copyfmt: Copy formatting information (public member function)

fill: Get/set fill character (public member function)

exceptions: Get/set exceptions mask (public member function)

imbue: Imbue locale (public member function)

tie: Get/set tied stream (public member function)

rdbuf: Get/set stream buffer (public member function)

narrow: Narrow character (public member function)

widen: Widen character (public member function)

Public member functions inherited from `ios_base`

flags: Get/set format flags (public member function)

setf: Set specific format flags (public member function)

unsetf: Clear specific format flags (public member function)

precision: Get/Set floating-point decimal precision (public member function)

width: Get/set field width (public member function)

imbue: Imbue locale (public member function)

getloc: Get current locale (public member function)

xalloc: Get new index for extensible array [static] (public static member function)

iword: Get integer element of extensible array (public member function)

pword: Get pointer element of extensible array (public member function)

register_callback: Register event callback function (public member function)

sync_with_stdio: Toggle synchronization with cstdio streams [static] (public static member function)

Non-member function overloads

swap: Swap output file streams (function template)

class templates

classes

public member functions

non-member overloads