std::mbsinit
From cppreference.com
Defined in header <cwchar> | ||
int mbsinit(conststd::mbstate_t* ps); | ||
If ps is not a null pointer, the mbsinit function determines whether the pointed-to std::mbstate_t object describes the initial conversion state.
Contents |
[edit]Notes
Although a zero-initialized std::mbstate_t always represents the initial conversion state, there may be other values of std::mbstate_t that also represent the initial conversion state.
[edit]Parameters
| ps | - | pointer to the std::mbstate_t object to examine |
[edit]Return value
0 if ps is not a null pointer and does not represent the initial conversion state, nonzero value otherwise.
[edit]Example
Run this code
#include <clocale>#include <cwchar>#include <iostream>#include <string> int main(){// allow mbrlen() to work with UTF-8 multibyte encodingstd::setlocale(LC_ALL, "en_US.utf8");// UTF-8 narrow multibyte encodingstd::string str ="水";// or u8"\u6c34" or "\xe6\xb0\xb4"std::mbstate_t mb =std::mbstate_t();(void)std::mbrlen(&str[0], 1, &mb);if(!std::mbsinit(&mb))std::cout<<"After processing the first 1 byte of "<< str <<" the conversion state is not initial\n"; (void)std::mbrlen(&str[1], str.size()-1, &mb);if(std::mbsinit(&mb))std::cout<<"After processing the remaining 2 bytes of "<< str <<", the conversion state is initial conversion state\n";}
Output:
After processing the first 1 byte of 水 the conversion state is not initial After processing the remaining 2 bytes of 水, the conversion state is initial conversion state
[edit]See also
| conversion state information necessary to iterate multibyte character strings (class) | |
C documentation for mbsinit | |
