C 字符串以零结尾，而 fortran 字符串按照惯例是用空格填充的，但大小固定.您不应该期望能够在不进行一些转换的情况下将 C 字符串传递给 fortran.

C strings are zero terminated whereas fortran strings, by convention, are space padded but of fixed size. You shouldn't expect to be able to pass C strings to fortran without some conversion.

例如:

#include <algorithm>

void ConvertToFortran(char* fstring, std::size_t fstring_len,
                      const char* cstring)
{
    std::size_t inlen = std::strlen(cstring);
    std::size_t cpylen = std::min(inlen, fstring_len);

    if (inlen > fstring_len)
    {
        // TODO: truncation error or warning
    }

    std::copy(cstring, cstring + cpylen, fstring);
    std::fill(fstring + cpylen, fstring + fstring_len, ' ');
}

然后您可以将其与 ftest 的 3 或 4 长度版本一起使用:

Which you can then use with either the 3 or 4 length version of ftest:

#include <iostream>
#include <ostream>
extern "C" int ftest_( char string[][4] );

void ConvertToFortran(char* fstring, std::size_t fstring_len,
                      const char* cstring);

int main()
{
    char cstring[2][4] = { "abc", "xyz" };
    char string[2][4];

    ConvertToFortran(string[0], sizeof string[0], cstring[0]);
    ConvertToFortran(string[1], sizeof string[1], cstring[1]);

    std::cout << "c++: string[0] = '" << cstring[0] << "'" << std::endl;
    std::cout << "c++: string[1] = '" << cstring[1] << "'" << std::endl;

    ftest_(string);

    return 0;
}