It seems like memcpy and memmove can't copy source string to destination string if the sizes are not the same. I have the following sgring

source x[27] and destination y[256]

I want to copy or move the contain of x to y, but keep getting error source is too small

memmove(y, x, 256);//keep getting error, x is 27 bytes too small

so how can I move the data