Constant UDIAG_SHOW_ICONS 

pub const UDIAG_SHOW_ICONS: u32 = _; // 8u32

The attribute reported in answer to this request is UNIX_DIAG_ICONS, which information about pending connections. Specifically, it contains the inode numbers of the sockets that have passed the connect(2) call, but hasn’t been processed with accept(2) yet. This attribute is reported for listening sockets only.