From ac83c85a9943c8215382652655d32af0bca94b7a Mon Sep 17 00:00:00 2001
From: Magnus Lundborg <lundborg.magnus@gmail.com>
Date: Fri, 24 Oct 2014 10:24:22 +0200
Subject: [PATCH] When writing TNG the input must contain molecule data.

When using trjcat to write TNG the input must also be TNG since
no tpr file is used.

Fixes #1626

Change-Id: I060e0174f9a471e134a4a899f83afaf02f4fce00
---
 src/gromacs/gmxana/gmx_trjcat.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/gromacs/gmxana/gmx_trjcat.c b/src/gromacs/gmxana/gmx_trjcat.c
index 629f221d0b..0e905041ce 100644
--- a/src/gromacs/gmxana/gmx_trjcat.c
+++ b/src/gromacs/gmxana/gmx_trjcat.c
@@ -651,6 +651,10 @@ int gmx_trjcat(int argc, char *argv[])
         {
             if (ftpout == efTNG)
             {
+                if (ftpout != ftpin)
+                {
+                    gmx_fatal(FARGS, "When writing TNG the input file format must also be TNG");
+                }
                 if (bIndex)
                 {
                     trjtools_gmx_prepare_tng_writing(out_file, 'w', NULL, &trxout,
-- 
2.22.0