def append_all(src_str, append, delimiter):
    """
    Add the append string into each split sub-strings of the
    first string(=src=). The split is performed into src string
    using the delimiter . E.g. appendAll("/a/b/,/c/b/,/c/d/", "ADD", ",")
    will return /a/b/ADD,/c/b/ADD,/c/d/ADD. A append string with null
    value is consider as an empty string. A delimiter string with value null
    is considered as no append in the string.
    """
    if not delimiter:
        return src_str
    if not append:
        append = ""

    split_str = src_str.split(delimiter)
    appended_list = []
    for split in split_str:
        appended_list.append(split + append)
    return delimiter.join(appended_list)