Sets the socket option requested. Returns undefined if there is an
error. Use integer constants provided by the Socket
module for
LEVEL and OPNAME. Values for LEVEL can also be obtained from
getprotobyname. OPTVAL might either be a packed string or an integer.
An integer OPTVAL is shorthand for pack("i", OPTVAL).
An example disabling Nagle's algorithm on a socket:
- use Socket qw(IPPROTO_TCP TCP_NODELAY);
- setsockopt($socket, IPPROTO_TCP, TCP_NODELAY, 1);