Index: src/libcschem/plug_io.c
===================================================================
--- src/libcschem/plug_io.c	(revision 10362)
+++ src/libcschem/plug_io.c	(revision 10363)
@@ -560,6 +560,11 @@
 
 				if (!preserve_name && ((stype == SS_SAVE_SHEET) || (stype == SS_SAVE_SHEET_AS_SYM))) {
 					char *newname = rnd_lrealpath(fn);
+					if (newname == NULL) {
+						rnd_message(RND_MSG_ERROR, "Failed to realpath(%s)\nMight be write permission problems\n", fn);
+						ret = -1;
+						goto error;
+					}
 					if ((sheet->hidlib.fullpath == NULL) || (strcmp(sheet->hidlib.fullpath, newname) != 0)) {
 						free(sheet->hidlib.fullpath);
 						sheet->hidlib.fullpath = newname;
@@ -586,6 +591,7 @@
 			break;
 	}
 
+	error:;
 	free(fn);
 	vtpr_uninit(&prios);
 	return ret;