Function blosc2_schunk_append_buffer 

pub unsafe extern "C" fn blosc2_schunk_append_buffer(
    schunk: *mut blosc2_schunk,
    src: *mut c_void,
    nbytes: i32,
) -> i64

@brief Append a @p src data buffer to a super-chunk.

@param schunk The super-chunk where data will be appended. @param src The buffer of data to compress. @param nbytes The size of the @p src buffer.

@return The number of chunks in super-chunk. If some problem is detected, this number will be negative.