add struct for usbtmc header

[rigol] / usbtmc.c

diff --git a/usbtmc.c b/usbtmc.c
index 622ea8099914c8f26746ef288d4e6483a8b29308..32f83a86d44ce4e0f413df5cc14ca2ef9f77dd1e 100644 (file)
--- a/usbtmc.c
+++ b/usbtmc.c
@@ -126,8 +126,7 @@ usb_dev_handle* usbtmc_initscope(void) {
        //Locate and open the scope
        dev = usbtmc_find_scope();
        if (!dev) {
-               printf("No scope found.\n");
-               exit(1);
+               return NULL;
        }
        usbtmc_claim(dev);
        //The following code isn't really necessary, the program works