From: "Christian Huitema" <huitema(_at_)windows(_dot_)microsoft(_dot_)com>
...
Well, that is emphatically *NOT* what application developers do.
Speak for yourself.
Which actually poses an interesting question: when should an application
just give up? IMHO, there is only one clear-cut case, i.e. when the
application actually contacted the peer and obtained an explicit
statement that the planned exchange should not take place -- the
equivalent of a 4XX or 5XX error in SMTP or HTTP.
I've written application code that shuts up for a while when it
receives an errno value that indicates that the kernel has received
an ICMP Unreachable.
The code I'm thinking of is fairly portable, and so I've also had to
#ifdef it to ignore error numbers that ought to indicate an Unreachable
but don't on some UNIX-like systems or are not reported.
Vernon Schryver vjs(_at_)rhyolite(_dot_)com