The VideoLAN Forums

Vector Linux 4.0 (Slackware based)
gcc version 3.3.6
kernel 2.4.29

Compilation ot the source code halted with undefined references to IPV6_V6ONLY.

This fixed the problem:
I added to the top of src/network/rootwrap.c:

#ifndef IPV6_V6ONLY
# define IPV6_V6ONLY 0
#endif

Compilation then completed normally.

This is not a proper fix; some parts of VLC will not work properly without this. And your libc is probably way out-of-date, so I'm not fixing this.

ldd /bin/sh
libtermcap.so.2 => /lib/libtermcap.so.2 (0x40026000)
libdl.so.2 => /lib/libdl.so.2 (0x4002b000)
libc.so.6 => /lib/libc.so.6 (0x4002e000)
/lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000)

ls -l /lib/libc.so.6
lrwxrwxrwx 1 root root 13 Nov 27 06:52 /lib/libc.so.6 -> libc-2.3.2.so*

I don't know the SO version numbers of glibc6. But in any case, not setting IPV6_V6ONLY on Linux will result in incorrect VLC semantics with regard to sockets.

glibc development headers have been defining this for several years now. You have to update your system.