[lib] Add comments regarding setsockopt_multicast_ipv4 arguments.
2007-07-06 Andrew J. Schorr <ajschorr@alumni.princeton.edu>
* sockopt.{c,h}: (setsockopt_multicast_ipv4) Add some comments about
the arguments.
diff --git a/lib/ChangeLog b/lib/ChangeLog
index 3a1d1f6..2d8e5de 100644
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,3 +1,8 @@
+2007-07-06 Andrew J. Schorr <ajschorr@alumni.princeton.edu>
+
+ * sockopt.{c,h}: (setsockopt_multicast_ipv4) Add some comments about
+ the arguments.
+
2007-06-01 Andrew J. Schorr <ajschorr@alumni.princeton.edu>
* zebra.h: On linux, we seem to need to include <linux/types.h> before
diff --git a/lib/sockopt.c b/lib/sockopt.c
index 6ddbded..f5f1a7e 100644
--- a/lib/sockopt.c
+++ b/lib/sockopt.c
@@ -176,9 +176,10 @@
int
setsockopt_multicast_ipv4(int sock,
int optname,
- struct in_addr if_addr,
+ struct in_addr if_addr /* required */,
unsigned int mcast_addr,
- unsigned int ifindex)
+ unsigned int ifindex /* optional: if non-zero, may be
+ used instead of if_addr */)
{
#ifdef HAVE_STRUCT_IP_MREQN_IMR_IFINDEX
diff --git a/lib/sockopt.h b/lib/sockopt.h
index d88bfa6..65ba34f 100644
--- a/lib/sockopt.h
+++ b/lib/sockopt.h
@@ -79,9 +79,12 @@
? SOPT_SIZE_CMSG_PKTINFO_IPV6())
extern int setsockopt_multicast_ipv4(int sock, int optname,
- struct in_addr if_addr,
+ struct in_addr if_addr
+ /* required: interface to join on */,
unsigned int mcast_addr,
- unsigned int ifindex);
+ unsigned int ifindex
+ /* optional: if non-zero, may be used
+ instead of if_addr */);
/* Ask for, and get, ifindex, by whatever method is supported. */
extern int setsockopt_ifindex (int, int, int);