std::setiosflags
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setiosflags
(C++14)
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.
[edit] Parameters
mask
-
bitmask of the flags to set
[edit] 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); }
[edit] 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
[edit] 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 streamsof type std::ostream or std::istream |
usable with any character stream |