Hmm, dann hab ich nur noch folgende Idee:
Das Quit wird an den SMTP Server übermittelt. Was ist wenn ein Quit#13#10 geschickt wird und "der" aktuell SMTP auf Linux läuft und dann die Verbindung nach dem #13 beendet, dass das "Broken Pipe" entsteht, weil das #10 noch durch will?
Du könntest also mal Loggen, bei welchen
SMTP Server das entsteht.
Edit:
In der
RFC steht CRLF
Code:
4.1.1.10. QUIT (QUIT)
This command specifies that the receiver MUST send a "221 OK" reply,
and then close the transmission channel.
The receiver MUST NOT intentionally close the transmission channel
until it receives and replies to a QUIT command (even if there was an
error). The sender MUST NOT intentionally close the transmission
channel until it sends a QUIT command, and it SHOULD wait until it
receives the reply (even if there was an error response to a previous
command). If the connection is closed prematurely due to violations
of the above or system or network failure, the server MUST cancel any
pending transaction, but not undo any previously completed
transaction, and generally MUST act as if the command or transaction
in progress had received a temporary error (i.e., a 4yz response).
The QUIT command may be issued at any time. Any current uncompleted
mail transaction will be aborted.
Syntax:
quit = "QUIT" CRLF
Evtl. das hier?
https://stackoverflow.com/questions/...pe-broken-pipe