Index: asymptote-2.47/settings.cc
===================================================================
--- asymptote-2.47/settings.cc
+++ asymptote-2.47/settings.cc	2018-10-02 00:07:37.797873559 +0200
@@ -91,11 +91,11 @@
 string HOME="HOME";
 string docdir=ASYMPTOTE_DOCDIR;
 const char pathSeparator=':';
-string defaultPSViewer="gv";
+string defaultPSViewer="xdg-open";
 #ifdef __APPLE__
 string defaultPDFViewer="open";
 #else  
-string defaultPDFViewer="acroread";
+string defaultPDFViewer="xdg-open";
 #endif  
 string defaultGhostscript="gs";
 string defaultGhostscriptLibrary="";