std::basic_ostream::write

 

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std::basic_ostream

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operator<<(std::basic_ostream)

 

basic_ostream& write( const char_type* s, std::streamsize count );

Behaves as an UnformattedOutputFunction. After constructing and checking the sentry object, outputs the characters from successive locations in the character array whose first element is pointed to by s. Characters are inserted into the output sequence until one of the following occurs:

• exactly count characters are inserted
• inserting into the output sequence fails (in which case setstate(badbit) is called)

Parameters

s	-	pointer to the character string to write
count	-	number of characters to write

Return value

*this

Notes

This function is not overloaded for the types signed char or unsigned char, unlike the formatted operator<<

Also, unlike the formatted output functions, this function does not set the failbit on failure.

Exceptions

If an exception occurs during output and exceptions() & badbit != 0, rethrows that exception.

If output fails and exceptions() & badbit != 0, throws ios_base::failure.

Example

This function may be used to output object representations, i.e. binary output

Run this code

#include <iostream>
 
int main()
{
    int n = 0x41424344;
    std::cout.write(reinterpret_cast<char*>(&n), sizeof n) << '\n';
 
    char c[]="This is sample text.";
    std::cout.write(c,4)<<'\n';
}

Output:

DCBA
This

See also

operator<<(std::basic_ostream)	inserts character data (function)
put	inserts a character (public member function)