Function is_unobserved_receive 

pub fn is_unobserved_receive(line: &str) -> bool

Whether line is one unobserved recvmsg buffer-digest record, as Detcore’s detlog_io_buffers writes it when a receive’s buffers cannot be observed after the call. The whole record is matched from the level onwards, with its producer module and structured kind, so text elsewhere (a pathname in a syscall record, say) cannot be counted. Tracing span context (name{fields}: groups, present under --verify-verbose or a trace log level) may sit between the level and the module.