#include <stdio.h>
#include <string.h>
#include <iconv.h>
#define N 64
 
void utf8c1251 (char *from, char *to)
{
    int fl, tl; 
    
    iconv_t d; 
    fl=tl=strlen(from); 
    d=iconv_open("CP1251","UTF-8"); 
    iconv(d, &from,&fl,&to,&tl); 
    iconv_close(d);                               
}
 
int main()
{
    char s[N] = "Привет", t[N] = "";
    
    utf8c1251(s, t);
    printf("s: %s\n", s);
    printf("t: %s\n", t);
    return 0;
}

1.cpp:25:2: warning: no newline at end of file
1.cpp: In function 'void utf8c1251(char*, char*)':
1.cpp:13: error: invalid conversion from 'char**' to 'const char**'
1.cpp:13: error:   initializing argument 2 of 'size_t libiconv(void*, const char**, size_t*, char**, size_t*)'
1.cpp:13: error: invalid conversion from 'int*' to 'size_t*'
1.cpp:13: error:   initializing argument 3 of 'size_t libiconv(void*, const char**, size_t*, char**, size_t*)'
1.cpp:13: error: invalid conversion from 'int*' to 'size_t*'
1.cpp:13: error:   initializing argument 5 of 'size_t libiconv(void*, const char**, size_t*, char**, size_t*)'