/* Hint #1: ENETUNREACH happens if we try to connect to "non-existing" special IP addresses, such as ::5.
*
* Hint #2: The kernel sends e.g., EHOSTUNREACH or ENONET to userspace in some ICMP error cases. See the
- * icmp_err_convert[] in net/ipv4/icmp.c in the kernel sources */
+ * icmp_err_convert[] in net/ipv4/icmp.c in the kernel sources.
+ *
+ * Hint #3: When asynchronous connect() on TCP fails because the host never acknowledges a single packet,
+ * kernel tells us that with ETIMEDOUT, see tcp(7). */
static inline bool ERRNO_IS_DISCONNECT(int r) {
return IN_SET(abs(r),
ECONNABORTED,
ENOTCONN,
EPIPE,
EPROTO,
- ESHUTDOWN);
+ ESHUTDOWN,
+ ETIMEDOUT);
}
/* Transient errors we might get on accept() that we should ignore. As per error handling comment in