buffer_putflush - write binary data to buffer and flush

       buffer_putflush is similar to calling buffer_put(b,x,len) and then buffer_flush(b).

       buffer_putflush - write binary data to buffer and flush

       0 if everything is fine, -1 on error (setting errno).

buffer_put(3), buffer_flush(3), buffer(3)

                                                                                              buffer_putflush(3)

#include<libowfat/buffer.h>

       int buffer_putflush(buffer* b,
                           const char* x,size_t len);