From c0f4048e84e3cc578f487e9d305728be7cce2525 Mon Sep 17 00:00:00 2001
From: Iain Buchanan <iain@corrosioninstruments.com>
Date: Fri, 14 Jan 2022 12:33:38 +0930
Subject: [PATCH] improve error message for incorrect file name/path

---
 gpssim.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/gpssim.c b/gpssim.c
index 6cb725b..148fc4c 100644
--- a/gpssim.c
+++ b/gpssim.c
@@ -1930,6 +1930,11 @@ int main(int argc, char *argv[])
 		fprintf(stderr, "ERROR: No ephemeris available.\n");
 		exit(1);
 	}
+	else if (neph==-1)
+	{
+		fprintf(stderr, "ERROR: ephemeris file not found.\n");
+		exit(1);
+	}
 
 	if ((verb==TRUE)&&(ionoutc.vflg==TRUE))
 	{