imap: Added clarification to the code about odd continuation responses

diff --git a/lib/imap.c b/lib/imap.c
index 5d3a1a17ebd31553dffe7dc013a517996f764223..9a845102ad704316e8c29fadfac9e7a6cdbf1764 100644 (file)
--- a/lib/imap.c
+++ b/lib/imap.c
@@ -336,7 +336,10 @@ static bool imap_endofresp(struct connectdata *conn, char *line, size_t len,
     return TRUE;
   }
 
-  /* Do we have a continuation response? */
+  /* Do we have a continuation response? This should be a + symbol followed by
+     a space and optionally some text as per RFC-3501 for the AUTHENTICATE and
+     APPEND commands and as outlined in Section 4. Examples of RFC-4959 but
+     some e-mail servers ignore this and only send a single + instead. */
   if((len == 3 && !memcmp("+", line, 1)) ||
      (len >= 2 && !memcmp("+ ", line, 2))) {
     switch(imapc->state) {