!TITLE  File Handling
!KEY

see(F)      File F becomes the current input stream.

seeing(F)   F is unified with the name of the current input file.

seen        Closes current input stream.

tell(F)     File F becomes the current output stream.

telling(F)  F is unified with the name of the current output file.

told        Closes the current output stream.

close(F)    File F, currently open for input or output, is closed.

fileerrors  Undoes the effect of nofileerrors.

nofileerrors
            After a call to this predicate, the I/O error conditions "incorrect
            file  name  ...",  "can't  see file ...", "can't tell file ..." and
            "end of file ..." cause a call  to  fail  instead  of  the  default
            action, which is to type an error message and then call abort.

exists(F)   Succeeds if the file F exists.

rename(F,N) If  file  F is currently open, it is closed and renamed to N.  If N
            is '[]', the file is deleted.