< cpp‎ | io‎ | manip
Input/output manipulators
Floating-point formatting
Integer formatting
Boolean formatting
Field width and fill control
Other formatting
Whitespace processing
Output flushing
Status flags manipulation
Time and money I/O
Quoted manipulator
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.


[edit] Parameters

c - new value for the fill character

[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 << 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

[edit] Notes

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

[edit] Example

#include <iostream>
#include <iomanip>
int main()
    std::cout << "default fill: [" << std::setw(10) << 42 << "]\n"
              << "setfill('*'): [" << std::setfill('*')
                                   << std::setw(10) << 42 << "]\n";


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

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

[edit] See also

manages the fill character
(public member function of std::basic_ios<CharT,Traits>) [edit]
sets the placement of fill characters
(function) [edit]
changes the width of the next input/output field
(function) [edit]