# std::setfill

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< cpp‎ | io‎ | manip

Defined in header `<iomanip>` |  |
template< class CharT > /*unspecified*/ setfill( CharT c ); |  |

When used in an expression out << setfill(c) sets the fill character of the stream out to c.

### Parameters

c | - | new value for the fill character

### Return value

An object of unspecified type such that

- if out is an object of type std::basic_ostream<CharT, Traits>, the expression out << setfill(c)
  - has type std::basic_ostream<CharT, Traits>&
  - has value out
  - behaves as if it called f(out, c)

where the function f is defined as:

    template<class CharT, class Traits>
    void f(std::basic_ios<CharT, Traits>& str, CharT c)
    {
        // set fill character
        str.fill(c);
    }

### Notes

The current fill character may be obtained with std::ostream::fill.

### Example

Run this code

    #include <iostream>
    #include <iomanip>

    int main()
    {
        std::cout << "default fill: [" << std::setw(10) << 42 << "]\n"
                  << "setfill('*'): [" << std::setfill('*')
                                       << std::setw(10) << 42 << "]\n";
    }

Output:

    default fill: [        42]
    setfill('*'): [********42]

### 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 | `setbase` could only be used with streams of type std::ostream | usable with any output character stream

### See also

fill | manages the fill character (public member function of `std::basic_ios<CharT,Traits>`)
internal left right | sets the placement of fill characters (function)
setw | changes the width of the next input/output field (function)

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