The programs saved in this fashion can be read back from file into memory by means of the read-command. Since we may in time forget the names of our files, it is possible to get a directory, i.e. list of file names. We obtain this by a somewhat roundabout way, viz. by trying to read a file that is definitively not there, e.g.
We can now inspect the directory to decide what is the name of the file we want to read.