yabasic problem

[Richard Owlett <rowlett@cloud85.net>]

I've installed yabasic from the repository.

I invoked as:> richard@debian-jan13:~$
> richard@debian-jan13:~$ yabasic
>
> This is yabasic version 2.78.0,
> built on i686-pc-linux-gnu at Mon Jan 23 14:17:02 UTC 2017
My code fragment is:
> infile$  = "/home/richard/Documents/cherrytree/edit_bookmarks/expermental_copies/prettytest0txt"
> outfile$ = "/home/richard/Documents/cherrytree/edit_bookmarks/expermental_copies/1stpass.txt"
> fd_in=open("/home/richard/Documents/cherrytree/edit_bookmarks/expermental_copies/prettytest0txt","r")
> print peek$("error")
> fd_out = open(outfile$,"w")
> print peek$("error")

For both print peek$("error") I'm told "No such file or directory".
The file to be read EXISTS and belongs to "richard"

I'm running the i386 flavor of Debian Stretch on a 686 machine [ThinkPad 
T510]

Suggestions?
TIA