Check that dirax,felix,mosflm or xds are available at the start

Avoids a confusing error message later.

1 files changed, 7 insertions, 0 deletions

diff --git a/libcrystfel/src/xds.c b/libcrystfel/src/xds.c
index a234d1e0..bd98aec4 100644
--- a/libcrystfel/src/xds.c
+++ b/libcrystfel/src/xds.c
@@ -45,6 +45,7 @@
 #include <sys/ioctl.h>
 #include <errno.h>
 
+#include "xds.h"
 #include "cell.h"
 #include "image.h"
 #include "utils.h"
@@ -596,6 +597,12 @@ void *xds_prepare(IndexingMethod *indm, UnitCell *cell)
 {
 	struct xds_private *xp;
 
+	if ( xds_probe(cell) == NULL ) {
+		ERROR("XDS does not appear to run properly.\n");
+		ERROR("Please check your XDS installation.\n");
+		return NULL;
+	}
+
 	/* Either cell,latt and cell provided, or nocell-nolatt and no cell
 	 * - complain about anything else.  Could figure this out automatically,
 	 * but we'd have to decide whether the user just forgot the cell, or