Don't crash on command lines without file/device name "... -i gdb -f".

diff --git a/gpsbabel/main.c b/gpsbabel/main.c
index 2e4b97e1b090ecb1a00f94a9f69b4674a95b9798..cca0d9a13c10f74d9b40c4c94415cf77bc5dfa20 100644 (file)
--- a/gpsbabel/main.c
+++ b/gpsbabel/main.c
@@ -331,6 +331,9 @@ main(int argc, char *argv[])
                                optarg = argv[argn][2]
                                        ? argv[argn]+2 : argv[++argn];
                                fname = optarg;
+                               if (fname == NULL) {
+                                       fatal ("No file or device name specified.\n");
+                               }
                                if (ivecs == NULL) {
                                        fatal ("No valid input type specified\n");
                                }
@@ -359,6 +362,9 @@ main(int argc, char *argv[])
                                optarg = argv[argn][2]
                                        ? argv[argn]+2 : argv[++argn];
                                ofname = optarg;
+                               if (ofname == NULL) {
+                                       fatal ("No output file or device name specified.\n");
+                               }
                                if (ovecs && (!(global_opts.masked_objective & POSNDATAMASK))) {
                                        /* simulates the default behaviour of waypoints */
                                        if (doing_nothing)