C programmer: Sequential Access file. Entering data into a file and outputting data from a file

A sequential access file is a file that does not have a structured approach to storing data, for example: all lines have different lengths, different numbers of spaces, some lines may be empty, and so on. In this regard, the file can only be read sequentially using the "fscanf" function. Each call to this function shifts the pointer position in the file to the next line until the end of the file is met.