cdm/src/main/java/ucar/nc2/iosp/NCheader.java
static boolean
    memequal(byte[] b1, byte[] b2, int len)
    {
        if(b1 == b2) return true;
        if(b1 == null || b2 == null) return false;
        if(b1.length < len || b2.length < len) return false;
        for(int i = 0; i < len; i++) {
            if(b1[i] != b2[i]) return false;
        }
        return true;
    }
static boolean
    memequal(byte[] b1, byte[] b2, int len)
    {
        if(b1 == b2) return true;
        if(b1 == null || b2 == null) return false;
        if(b1.length < len || b2.length < len) return false;
        for(int i = 0; i < len; i++) {
            if(b1[i] != b2[i]) return false;
        }
        return true;
    }
Not quite memcmp

@param b1
@param b2
@param len
@return