std::streamsize gcount() const; |
Returns the number of characters extracted by the last unformatted input operation, or the maximum representable value of std::streamsize
if the number is not representable.
The following member functions of basic_istream
change the value of subsequent gcount()
calls:
The following functions set gcount()
to zero:
(none).
The number of characters extracted by the last unformatted input operation, or the maximum representable value of std::streamsize
if the number is not representable.
#include <iostream> #include <sstream> int main() { char x[20]; std::istringstream stream("Hello World"); stream.read(x, sizeof x); std::cout << "Characters extracted: " << stream.gcount(); }
Output:
Characters extracted: 11
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR | Applied to | Behavior as published | Correct behavior |
---|---|---|---|
LWG 3464 | C++98 | the return value was unspecified when the result overflows | returns the maximum value |
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