561: Highlights

• If you want to tell C that you intend to work with input or output files, then include the following line in your program:

  #include 
  

• If you want to open an input file, then instantiate the following pattern:

  FILE* file-pointer name; 
  file-pointer name = fopen(file specification, "r"); 
  

• If you want to open an output file, then instantiate the following pattern:

  FILE* file-pointer name; 
  file-pointer name = fopen(file specification, "w"); 
  

• If you want to read data from an open input file, then substitute fscanf for scanf, and add a file pointer as the first argument.
• If you want to write data into an open output file, then substitute fprintf for printf, and add a file pointer as the first argument.
• If you are finished with an input or output file, then you should close it by instantiating the following pattern:

  fclose (file-pointer name);