NAME¶

std::setiosflags - std::setiosflags

Synopsis¶

Defined in header <iomanip>
/*unspecified*/ setiosflags( std::ios_base::fmtflags mask );

When used in an expression out << setiosflags(mask) or in >> setiosflags(mask), sets
all format flags of the stream out or in as specified by the mask.

Parameters¶

mask - bitmask of the flags to set

Return value¶

An object of unspecified type such that

* if out is an object of type std::basic_ostream<CharT, Traits>, the expression
out << setiosflags(mask)
* has type std::basic_ostream<CharT, Traits>&
* has value out
* behaves as if it called f(out, mask)
* if in is an object of type std::basic_istream<CharT, Traits>, the expression in
>> setiosflags(mask)
* has type std::basic_istream<CharT, Traits>&
* has value in
* behaves as if it called f(in, mask)

where the function f is defined as:

void f(std::ios_base& str, std::ios_base::fmtflags mask)
{
// set specified flags
str.setf(mask);
}

Example¶

// Run this code

#include <iomanip>
#include <iostream>

int main()
{
std::cout << std::resetiosflags(std::ios_base::dec)
<< std::setiosflags( std::ios_base::hex
| std::ios_base::uppercase
| std::ios_base::showbase) << 42 << '\n';
}

Output:¶

0X2A

Defect reports

The following behavior-changing defect reports were applied retroactively to
previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 183 C++98 setiosflags could only be used with streams usable with any
of type std::ostream or std::istream character stream

See also¶

setf sets specific format flag
(public member function of std::ios_base)
resetiosflags clears the specified ios_base flags
(function)