Странное поведение netcat (версия OpenBSD)

 # for each file in the current directory you can refine the ls command to match 
 # only the files you want. or if in a script file pass in the file list 
 for file in *
 do
    # if the file has more than 10 lines.
    if (( $(<"${file}" wc -l) > 10 )); then
       # print line 3 to end of file and pipe it to a file with the same
       # name as the input file with the added .checked at the end.
       sed -n '3,$p' -- "${file}" > "${file}.checked"
    fi
 done