Option P -- Screen paging.  "YES" will cause FILESIZE to pause each time 
the screen fills by default.  "NO" will default to continuous scrolling.  
The P command line option toggles the selected default.

Option S -- Include system files.  "NO" causes system files to be ignored 
by default.  If "YES" is selected, system files will be included in the 
search.  The S command line option toggles the selected default.

Option N -- Number of files.  Each matched filename requires 15 bytes of 
buffer space, or about 15k per 1000 matches.  If memory is limited, you 
will need to reduce the number of files allowed.

Option L -- Screen lines.  This value is only used under vanilla CP/M.  
Under ZCPR3 the number of screen lines is obtained from the environment 
descriptor.  Enter the actual number of lines on your screen.