Lookup.cgi: Error result.

can't read "line": no such variable

Stack trace:

can't read "line": no such variable
    while executing
"set line"
    ("eval" body line 1)
    invoked from within
"eval set line $result"
    (procedure "Perform_search" line 31)
    invoked from within
"Perform_search"
    (procedure "Main" line 5)
    invoked from within
"Main"