Definition and analysis of flow state in iOS _c language

1:iostate rdstate () const; The return is iostate, which is simply an int value. Set to 1 in a position of 2 data to indicate a state

2: Thedefinition of failbit is as follows, when the second digit of binary data is 1, the data is indicated.

static const _iostate Goodbit = (_iostate) 0x0; static const _iostate Eofbit = (_iostate) 0x1; static const _iostate Failbit = (_iostate) 0x2; static const _iostate Badbit = (_iostate) 0x4; static const _iostate _hardfail = (_iostate) 0x10;

3:input.rdstate () & Std::ios::failbit Determines whether the current state is failbit by the bitwise operation.