change walk to use exceptions instead of error strings

1 files changed, 4 insertions, 2 deletions

diff --git a/src/main/kotlin/ProtocolTranslator.kt b/src/main/kotlin/ProtocolTranslator.kt
index 1b45252..bf29131 100644
--- a/src/main/kotlin/ProtocolTranslator.kt
+++ b/src/main/kotlin/ProtocolTranslator.kt
@@ -67,9 +67,11 @@ interface ProtocolTranslator {
      * @param newfid The proposed FID, which is going to be associated with the result of walking the hierarchy. It must
      * be not in use, unless it is the same as [fid].
      * @param wname The successive path name elements which describe the file to walk to.
-     * @return a possible error.
+     * @throws except.InvalidMessageException if the received message is invalid.
+     * @throws except.RErrorException if the received message is an R-error message.
+     * @throws except.UnaccessibleFileException if [wname] contains one or more files that do not exist.
      */
-    fun walk(fid: UInt, newfid: UInt, wname: List<String>): String?
+    fun walk(fid: UInt, newfid: UInt, wname: List<String>)
 
     /**
      * Prepare an FID for I/O on an existing file.