Input/output manipulators

 

C++

Compiler support

Freestanding and hosted

Language

Standard library

Standard library headers

Named requirements

Feature test macros (C++20)

Language support library

Concepts library (C++20)

Diagnostics library

Memory management library

Metaprogramming library (C++11)

General utilities library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Strings library

Text processing library

Numerics library

Date and time library

Input/output library

Filesystem library (C++17)

Concurrency support library (C++11)

Execution control library (C++26)

Technical specifications

Symbols index

External libraries

 

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

basic_ostream

basic_iostream

File I/O

basic_ifstream

basic_ofstream

basic_fstream

String I/O

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)

 

Input/output manipulators

Floating-point formatting
showpointnoshowpoint setprecision	fixedscientifichexfloatdefaultfloat (C++11)(C++11)
Integer formatting
setbase showbasenoshowbase	dechexoct
Boolean formatting
boolalphanoboolalpha
Field width and fill control
setfill setw	internalleftright
Other formatting
showposnoshowpos	uppercasenouppercase
Whitespace processing
ws ends	skipwsnoskipws
Output flushing
flush endl flush_emit (C++20)	unitbufnounitbuf emit_on_flushnoemit_on_flush (C++20)(C++20)
Status flags manipulation
resetiosflags	setiosflags
Time and money I/O
get_money (C++11) get_time (C++11)	put_money (C++11) put_time (C++11)
Quoted manipulator
quoted (C++14)

 

Manipulators are helper functions that make it possible to control input/output streams using operator<< or operator>>.

The manipulators that are invoked without arguments (e.g. std::cout << std::boolalpha; or std::cin >> std::hex;) are implemented as functions that take a reference to a stream as their only argument. The special overloads of basic_ostream::operator<< and basic_istream::operator>> accept pointers to these functions. These functions (or instantiations of function templates) are the only addressable functions in the standard library.(since C++20)

The manipulators that are invoked with arguments (e.g. std::cout << std::setw(10);) are implemented as functions returning objects of unspecified type. These manipulators define their own operator<< or operator>> which perform the requested manipulation.

Defined in header <ios>
boolalphanoboolalpha	switches between textual and numeric representation of booleans (function)
showbasenoshowbase	controls whether prefix is used to indicate numeric base (function)
showpointnoshowpoint	controls whether decimal point is always included in floating-point representation (function)
showposnoshowpos	controls whether the + sign used with non-negative numbers (function)
skipwsnoskipws	controls whether leading whitespace is skipped on input (function)
uppercasenouppercase	controls whether uppercase characters are used with some output formats (function)
unitbufnounitbuf	controls whether output is flushed after each operation (function)
internalleftright	sets the placement of fill characters (function)
dechexoct	changes the base used for integer I/O (function)
fixedscientifichexfloatdefaultfloat (C++11)(C++11)	changes formatting used for floating-point I/O (function)
Defined in header <istream>
ws	consumes whitespace (function template)
Defined in header <ostream>
ends	outputs '\0' (function template)
flush	flushes the output stream (function template)
endl	outputs '\n' and flushes the output stream (function template)
emit_on_flushnoemit_on_flush (C++20)	controls whether a stream's basic_syncbuf emits on flush (function template)
flush_emit (C++20)	flushes a stream and emits the content if it is using a basic_syncbuf (function template)
Defined in header <iomanip>
resetiosflags	clears the specified ios_base flags (function)
setiosflags	sets the specified ios_base flags (function)
setbase	changes the base used for integer I/O (function)
setfill	changes the fill character (function template)
setprecision	changes floating-point precision (function)
setw	changes the width of the next input/output field (function)
get_money (C++11)	parses a monetary value (function template)
put_money (C++11)	formats and outputs a monetary value (function template)
get_time (C++11)	parses a date/time value of specified format (function template)
put_time (C++11)	formats and outputs a date/time value according to the specified format (function template)
quoted (C++14)	inserts and extracts quoted strings with embedded spaces (function template)