writev

#include < sys/uio.h >
#include < stdio.h >

int main()
{
    ssize_t n;
    struct iovec vector[3];
    
    vector[0].iov_base = "Hello";
    vector[0].iov_len = 5;
    
    vector[1].iov_base = " ";
    vector[1].iov_len = 1;
    vector[2].iov_base = "World\n";
    vector[2].iov_len = 6;
    
    if ((n = writev(1, vector, 3))< 0){
        perror("writev");
        return 1;
    }
    return 0;
}