From 9c19f98d58b299376cfa84d4412173e11f764793 Mon Sep 17 00:00:00 2001
From: "Eric S. Raymond" <esr@thyrsus.com>
Date: Tue, 11 Nov 2014 00:32:44 -0500
Subject: [PATCH] Further in an unlocked direction.  All regression tests pass.

---
 src | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src b/src
index 38743d7..f9214cf 100755
--- a/src
+++ b/src
@@ -940,8 +940,14 @@ class RCS:
         do_or_die("rcs -q -U -kb -i {0} </dev/null && mv {0},v {1}".format(arg, repodir))
     def checkin(self, arg, comment):
         "Check in a commit, with comment."
-        # Relies on caller to escape comment string
-        do_or_die("ci -l -m{1} {0}".format(arg, comment))
+        # Relies on caller to escape comment string.  By unlocking the
+        # file before checkin we invoke the following property
+        # described on the rcs(1) manual page: "If rev is omitted and
+        # the caller has no lock, but owns the file and locking is not
+        # set to strict, then the revision is appended to the default
+        # branch (normally the trunk; see the -b option of rcs(1))."
+        # This is the behavior we want and why locking is set to non-strict.
+        do_or_die("rcs -q -U -u {0},v && ci -l -m{1} {0}".format(arg, comment))
     def checkout(self, arg, revision):
         "Check out a revision. Leaves it writeable."
         do_or_die("rm -f {0} && rcs -q -u {0},v && co -q -l{1} {0}".format(arg, revision))
-- 
2.43.0