Thanks for help with validspamobject

I'm curious about a warning coming from the use of package sqldf.  I opened
a file and read it using a SQLite select statement:

f = "/Users/ronaldbarry/Desktop/Three-Dee/LakeMichDepth.txt"

sql_statement = "select long,lat,depth,(lat - 41.62) as templat, (long +
88) as templong
from file
where (abs(templat - 0.1*round(templat/0.1,0)) < 0.01)and(abs(templong -
0.15*round(templong/0.15,0)) < 0.01)"
Mich_depth = sqldf::read.csv.sql(file=f,sql =
sql_statement,header=TRUE,sep=' ')

Which ran perfectly well, but it threw a warning:

Warning messages:
1: In stopifnot(is.list(hooks)) :
  closing unused connection 6
(/Users/ronaldbarry/Desktop/Three-Dee/LakeMichDepth.txt)
2: In stopifnot(is.list(hooks)) :
  closing unused connection 5
(/Users/ronaldbarry/Desktop/Three-Dee/LakeMichDepth.txt)

It looks like it would be good practice to close the connection in code,
but I don't see any function in sqldf

to do so.  Is there a way to nicely close the connection, or should I just
ignore the warning?  Operating

system is Mac OSX 13.16 High Sierra, R Studio version 1.1.146, R version
3.5.0.  Thanks for any info.

Hi,
  Thanks for all your help.  The problem with an error involving
validspamobject() has been resolved, as a new version of spdep (0.7-7) was
just released and it seems to have stopped using the deprecated function.

Ron B.