--- pgpewrap.c | 4 ++++ 1 file changed, 4 insertions(+) --- pgpewrap.c +++ pgpewrap.c 2016-05-12 11:48:02.259503685 +0000 @@ -58,6 +58,10 @@ int main(int argc, char **argv) { } *opt = NULL; + if (opts[0] == NULL) { + fprintf(stderr, "Command line usage: %s [flags] -- prefix [recipients]\n", argv[0]); + return 1; + } execvp(opts[0], opts); perror(argv[0]); return 2;