From 3a4dfe37362e0d0a3e1ae34af0240c5ac46588d1 Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <richard@matrix.org>
Date: Tue, 25 May 2021 10:57:19 +0100
Subject: [PATCH] Improve the error message printed by synctl when synapse
 fails to start.

---
 changelog.d/10059.misc |  1 +
 synctl                 | 12 ++++++++----
 2 files changed, 9 insertions(+), 4 deletions(-)
 create mode 100644 changelog.d/10059.misc

diff --git a/changelog.d/10059.misc b/changelog.d/10059.misc
new file mode 100644
index 000000000000..ca6e0e8a5aff
--- /dev/null
+++ b/changelog.d/10059.misc
@@ -0,0 +1 @@
+Improve the error message printed by synctl when synapse fails to start.
diff --git a/synctl b/synctl
index 6ce19918d212..90559ded62e6 100755
--- a/synctl
+++ b/synctl
@@ -97,11 +97,15 @@ def start(pidfile: str, app: str, config_files: Iterable[str], daemonize: bool)
         write("started %s(%s)" % (app, ",".join(config_files)), colour=GREEN)
         return True
     except subprocess.CalledProcessError as e:
-        write(
-            "error starting %s(%s) (exit code: %d); see above for logs"
-            % (app, ",".join(config_files), e.returncode),
-            colour=RED,
+        err = "%s(%s) failed to start (exit code: %d). Check the Synapse logfile" % (
+            app,
+            ",".join(config_files),
+            e.returncode,
         )
+        if daemonize:
+            err += ", or run synctl with --no-daemonize"
+        err += "."
+        write(err, colour=RED, stream=sys.stderr)
         return False