notmuch: Document the new special-case syntax of "*".

This functionality came through a recent addition to the library.

1 files changed, 3 insertions, 0 deletions

diff --git a/notmuch.c b/notmuch.c
index 86509515..7e595e24 100644
--- a/notmuch.c
+++ b/notmuch.c
@@ -44,6 +44,9 @@ static const char search_terms_help[] =
     "\tthe given terms/phrases in the body, the subject, or any of\n"
     "\tthe sender or recipient headers.\n"
     "\n"
+    "\tAs a special case, a search string consisting of exactly a\n"
+    "\tsingle asterisk (\"*\") will match all messages.\n"
+    "\n"
     "\tIn addition to free text, the following prefixes can be used\n"
     "\tto force terms to match against specific portions of an email,\n"
     "\t(where <brackets> indicate user-supplied values):\n"