close -- close a file, which has been opened before

 
close filenum 
close # filenum
close -2
close #-2 

The close-command closes an open file. You should issue this command as soon as you are done with reading from or writing to a file.

close -2 closes all open files. 

all = -2
open "my.data" for reading as 1 
input #1 a 
print a 
close all 

This program opens the file "my.data", reads a number from it, prints this number and then closes all files.