add a note that SO_BINDTODEVICE needs padded iface name on 2.6.26

1 files changed, 3 insertions, 1 deletions

diff --git a/libbb/xconnect.c b/libbb/xconnect.c
index d078e9811..2eb4cb9be 100644
--- a/libbb/xconnect.c
+++ b/libbb/xconnect.c
@@ -24,7 +24,9 @@ int FAST_FUNC setsockopt_bindtodevice(int fd, const char *iface)
         int r;
         struct ifreq ifr;
         strncpy_IFNAMSIZ(ifr.ifr_name, iface);
-        /* Actually, ifr_name is at offset 0, and in practice
+        /* NB: passing (iface, strlen(iface) + 1) does not work!
+         * (maybe it works on _some_ kernels, but not on 2.6.26)
+         * Actually, ifr_name is at offset 0, and in practice
          * just giving char[IFNAMSIZ] instead of struct ifreq works too.
          * But just in case it's not true on some obscure arch... */
         r = setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr));