std::skipws, std::noskipws

 

C++

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Input/output manipulators

Floating-point formatting
showpointnoshowpoint setprecision	fixedscientifichexfloatdefaultfloat (C++11)(C++11)
Integer formatting
setbase showbasenoshowbase	dechexoct
Boolean formatting
boolalphanoboolalpha
Field width and fill control
setfill setw	internalleftright
Other formatting
showposnoshowpos	uppercasenouppercase
Whitespace processing
ws ends	skipwsnoskipws
Output flushing
flush endl flush_emit (C++20)	unitbufnounitbuf emit_on_flushnoemit_on_flush (C++20)(C++20)
Status flags manipulation
resetiosflags	setiosflags
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get_money (C++11) get_time (C++11)	put_money (C++11) put_time (C++11)
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quoted (C++14)

 

Defined in header <ios>
std::ios_base& skipws( std::ios_base& str );	(1)
std::ios_base& noskipws( std::ios_base& str );	(2)

Enables or disables skipping of leading whitespace by the formatted input functions (enabled by default). Has no effect on output.

1) enables the skipws flag in the stream str as if by calling str.setf(std::ios_base::skipws)

2) disables the skipws flag in the stream str as if by calling str.unsetf(std::ios_base::skipws)

The whitespace skipping is performed by the constructor of std::basic_istream::sentry, which reads and discards the characters classified as whitespace by the std::ctype facet of the stream's imbued locale.

This is an I/O manipulator, it may be called with an expression such as out << std::noskipws for any out of type std::basic_ostream or with an expression such as in >> std::noskipws for any in of type std::basic_istream.

Parameters

str

-

reference to I/O stream

Return value

str (reference to the stream after manipulation)

Example

Run this code

#include <iostream>
#include <sstream>
int main()
{
    char c1, c2, c3;
    std::istringstream("a b c") >> c1 >> c2 >> c3;
    std::cout << "Default  behavior: c1 = " << c1 << " c2 = " << c2 << " c3 = " << c3 << '\n';
    std::istringstream("a b c") >> std::noskipws >> c1 >> c2 >> c3;
    std::cout << "noskipws behavior: c1 = " << c1 << " c2 = " << c2 << " c3 = " << c3 << '\n';
}

Output:

Default  behavior: c1 = a c2 = b c3 = c
noskipws behavior: c1 = a c2 =   c3 = b

See also

resetiosflags	clears the specified ios_base flags (function)
setiosflags	sets the specified ios_base flags (function)
ws	consumes whitespace (function template)