libbb: make bb_lookup_port() abort on bad port names

Also, no need to preserve errno

function                                             old     new   delta
.rodata                                           104247  104241      -6
bb_lookup_port                                        97      83     -14
nc_main                                             1039    1018     -21
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-41)             Total: -41 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/networking/nc.c b/networking/nc.c
index 705b7356a..d351bf72a 100644
--- a/networking/nc.c
+++ b/networking/nc.c
@@ -216,7 +216,7 @@ int nc_main(int argc, char **argv)
                                 close(sfd);
                 } else {
                         cfd = create_and_connect_stream_or_die(argv[0],
-                                argv[1] ? bb_lookup_port(argv[1], "tcp", 0) : 0);
+                                bb_lookup_port(argv[1], "tcp", 0));
                 }
         }