}

      if {[file isdirectory $subDirectory]} then {
        foreach fileNameOnly $openPgpFileNamesOnly {
          set fileName [file join $subDirectory $fileNameOnly]

          if {[file exists $fileName] && [file isfile $fileName]} then {
            pkgLog [appendArgs \
                "the OpenPGP directory is being initialized to \"" \
                $subDirectory "\" based on OpenPGP file name \"" \
                $fileNameOnly \"]

            return [addToPath $subDirectory]
          }
        }
      }
    }

    return false

      Alternatively, it may be possible to install GNU Privacy Guard (GPG) via
      the package management subsystem included with your operating system.
    }

    set found false

    foreach fileName $openPgpFileNamesOnly {
    foreach fileNameOnly $openPgpFileNamesOnly {
      if {[isEagle]} then {
        if {[catch {
          eval exec -success Success [subst $openPgpInstalledCommand]
        } result] == 0} then {
          set found true; break
        }
      } else {

      #       viable OpenPGP file name?
      #
      if {[info exists openPgpFileNameOnly]} then {
        #
        # NOTE: If the OpenPGP file name that we found before (?) does not
        #       match what we already have, issue a log message.
        #
        if {$fileName ne $openPgpFileNameOnly} then {
        if {$fileNameOnly ne $openPgpFileNameOnly} then {
          pkgLog [appendArgs \
              "the OpenPGP file name is being changed from \"" \
              $openPgpFileNameOnly "\" to \"" $fileName \"]
              $openPgpFileNameOnly "\" to \"" $fileNameOnly \"]

          set openPgpFileNameOnly $fileName
          set openPgpFileNameOnly $fileNameOnly
        }
      } else {
        #
        # NOTE: Configure the OpenPGP file name to the one that was just
        #       found.
        #
        pkgLog [appendArgs \
            "the OpenPGP file name is being initialized to \"" \
            $fileNameOnly \"]

        set openPgpFileNameOnly $fileName
        set openPgpFileNameOnly $fileNameOnly
      }
    } else {
      #
      # NOTE: If no viable OpenPGP file name was found, raise the error
      #       message.
      #
      error $message

    #       sub-directory is relative to the "Program Files" directory.
    #
    variable openPgpInstalledDirectories; # DEFAULT: [list ...]

    if {$force || ![info exists openPgpInstalledDirectories]} then {
      if {[isWindows]} then {
        set openPgpInstalledDirectories [list \
            [file join gnupg] [file join GNU GnuPG]]
            [file join gnupg bin] [file join GNU GnuPG]]
      } else {
        set openPgpInstalledDirectories [list \
            [file join / usr bin]]
      }
    }

    #

    # NOTE: The command to use when attempting to verify that OpenPGP is
    #       installed locally.  This must be configured according to the
    #       implementation of OpenPGP in use.
    #
    variable openPgpInstalledCommand; # DEFAULT: gpg2 --version --homedir {}

    if {$force || ![info exists openPgpInstalledCommand]} then {
      set openPgpInstalledCommand {{${fileName}} --version --homedir {}}
      set openPgpInstalledCommand {{${fileNameOnly}} --version --homedir {}}
    }

    #
    # NOTE: The regular expression pattern used when attempting to verify
    #       that OpenPGP is installed locally.  This must be configured
    #       according to the implementation of OpenPGP in use.
    #