std::resetiosflags

 

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

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

Parameters

mask

-

bitmask of the flags to clear

Return value

An object of unspecified type such that

• if out is an object of type std::basic_ostream<CharT, Traits>, the expression out << resetiosflags(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 >> resetiosflags(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){// reset specified flags str.setf(ios_base::fmtflags(0), mask);}

Example

Run this code

#include <iomanip>#include <iostream>#include <sstream>   int main(){std::istringstream in("10 010 10 010 10 010");int n1, n2;   in >>std::oct>> n1 >> n2;std::cout<<"Parsing \"10 010\" with std::oct gives: "<< n1 <<' '<< n2 <<'\n';   in >>std::dec>> n1 >> n2;std::cout<<"Parsing \"10 010\" with std::dec gives: "<< n1 <<' '<< n2 <<'\n';   in >> std::resetiosflags(std::ios_base::basefield)>> n1 >> n2;std::cout<<"Parsing \"10 010\" with autodetect gives: "<< n1 <<' '<< n2 <<'\n';}

Output:

Parsing "10 010" with std::oct gives: 8 8 Parsing "10 010" with std::dec gives: 10 10 Parsing "10 010" with autodetect gives: 10 8

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	resetiosflags could only be used with streams of type std::ostream or std::istream	usable with any character stream

See also

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