protected virtual member function
<streambuf> <iostream>
streamsize xsputn (const char* s, streamsize n);
Put sequence of characters
Writes characters from the array pointed to by s into the controlled output sequence, until either n characters have been written or the end of the output sequence is reached.
Its default behavior in
streambuf is to call
sputc n times, stopping if any call returns
EOF.
Its default behavior in
streambuf is to retrieve
n characters, as if calling
sputc for each, stopping if any call would return
EOF. Except it is unspecified whether member
overflow is called or whether other means are used in case of
overflows.
This is a virtual member function, and derived classes may provide a more efficient implementation.
Parameters
- s
- Pointer to the sequence of characters to be written.
Member type char_type is the type of the characters in the stream buffer (the first class template parameter).
- n
- Number of characters to write.
This shall be a non-negative value.
streamsize is a signed integral type.
Return Value
The number of characters written.
streamsize is a signed integral type.
Data races
Accesses up to all of the first n characters in the array pointed by s.
Modifies the stream buffer object.
Concurrent access to the same array or to the same stream buffer object may introduce data races.
Exception safety
Basic guarantee: if an exception is thrown, the stream buffer is in a valid state (this also applies to standard derived classes).
Invalid arguments cause undefined behavior.