main: Check for at least one option

1 files changed, 6 insertions, 0 deletions

diff --git a/src/main.c b/src/main.c
index b83e35f..7a0efd5 100644
--- a/src/main.c
+++ b/src/main.c
@@ -205,6 +205,12 @@ main(int argc, char *argv[])
 		_help_tip(program_name);
 		return EXIT_FAILURE;
 	}
+	if (control_files == NULL && list_members == 0) {
+		fprintf(stderr, "%s: At least one of -I, -f, or -c must be "
+				"given\n", program_name);
+		_help_tip(program_name);
+		return EXIT_FAILURE;
+	}
 
 	/* Initialize outer archive. */
 	opk = opkg_opk_opk_init(argv[0]);