verifyPersistentRootDirectory
      set persistentDirectory $persistentRootDirectory
    }

    set persistent [string is true -strict \
        [getDictionaryValue $options -persistent]]

    set overwrite [string is true -strict \
        [getDictionaryValue $options -overwrite]]

    set usePgp [string is true -strict \
        [getDictionaryValue $options -usePgp]]

    set useAutoPath [string is true -strict \
        [getDictionaryValue $options -useAutoPath]]

    set allowUpdate [string is true -strict \

          $directory(temporary) $fileNameOnly]]

      if {[file exists $downloadFileName]} then {
        error [appendArgs \
            "temporary file name \"" $downloadFileName \
            "\" already exists"]
      }

      if {$persistent || $viaInstall} then {
        if {!$overwrite} then {
          set persistentFileName [file normalize [file join \
              $directory(persistent) $fileNameOnly]]

          if {[file exists $persistentFileName]} then {
            continue
          }
        }
      }

      file mkdir [file dirname $downloadFileName]

      downloadOneFile $language $version $platform \
          $fileName $downloadFileName $usePgp

      lappend downloadedFileNames [list \