I just modified mail-filter-out.sh like this:
cat  mail-filter-out.sh
  #!/bin/sh

  USER=$1
  cat > /tmp/tempfile
  cat /tmp/tempfile

cat  /tmp/tempfile
This message is in MIME format.

--nsmail-7bjyg3nr5o-7bmibqhut9
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: base64

PHA+Jm5ic3A7PC9wPjxwPiZuYnNwOzIxMjEyMTIxPC9wPjxwPiZuYnNwOzwv
cD48cD4mbmJzcDs8L3A+PHA+Jm5ic3A7PC9wPjxwPiZuYnNwOzwvcD4tLS0t
PGRpdiBpZD0iY3MyY19tYWlsX3NpZ2F0dXJlIj48L2Rpdj48cD48L3A+

--nsmail-7bjyg3nr5o-7bmibqhut9--

But the log appears:
  Feb 08 19:14:18 lda(q1@a.com)<71012><m+U/KQqYPl5kFQEA0J78UA>: Panic: file ostream.c: line 201 (o_stream_flush): assertion failed: (stream->stream_errno != 0)
  Feb 08 19:14:18 lda(q1@a.com)<71012><m+U/KQqYPl5kFQEA0J78UA>: Error: Raw backtrace: /opt/svn/nsmail-dovecot-2.3.9_4/src/lib- dovecot/.libs/libdovecot.so.0(backtrace_append+0x42) [0x7f60cc7cc5c2] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-dovecot/.libs/libdovecot.so.0(backtrace_get+0x1e) [0x7f60cc7cc6ce] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-dovecot/.libs/libdovecot.so.0(+0xe4bae) [0x7f60cc7d6bae] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-dovecot/.libs/libdovecot.so.0(+0xe4bf1) [0x7f60cc7d6bf1] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-dovecot/.libs/libdovecot.so.0(i_fatal+0) [0x7f60cc733628] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-dovecot/.libs/libdovecot.so.0(+0x10bc67) [0x7f60cc7fdc67] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-storage/.libs/libdovecot-storage.so.0(dbox_save_end+0x35) [0x7f60ccb032e5] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-storage/.libs/libdovecot-storage.so.0(mdbox_save_finish+0x39) [0x7f60ccaf7f99] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-lda/.libs/libdovecot-lda.so.0(+0x402e) [0x7f60ccdec02e] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-storage/.libs/libdovecot-storage.so.0(mailbox_save_finish+0x73) [0x7f60ccade4b3] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-storage/.libs/libdovecot-storage.so.0(mail_storage_copy+0xc9) [0x7f60ccad08f9] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-storage/.libs/libdovecot-storage.so.0(mdbox_copy+0x46) [0x7f60ccaf8816] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-lda/.libs/libdovecot-lda.so.0(+0x3e1a) [0x7f60ccdebe1a] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-storage/.libs/libdovecot-storage.so.0(+0x4e89c) [0x7f60ccade89c] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-lda/.libs/libdovecot-lda.so.0(mail_deliver_save+0x1d7) [0x7f60ccded457] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lib-lda/.libs/libdovecot-lda.so.0(mail_deliver+0x2fe) [0x7f60ccdedc6e] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lda/.libs/lt-dovecot-lda(main+0x644) [0x55e0340b3144] -> /lib64/libc.so.6(__libc_start_main+0xf5) [0x7f60cc350c05] -> /opt/svn/nsmail-dovecot-2.3.9_4/src/lda/.libs/lt-dovecot-lda(+0x3cb6) [0x55e0340b3cb6]



------------------ Original ------------------
From: "dovecot-request"<dovecot-request@dovecot.org>;
Date: Sat, Feb 8, 2020 06:00 PM
To: "dovecot"<dovecot@dovecot.org>;
Subject: dovecot Digest, Vol 202, Issue 11

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Today's Topics:

   1. Re: mail_filter plugin: failed: EOF without input (Gedalya)


----------------------------------------------------------------------

Message: 1
Date: Fri, 7 Feb 2020 23:48:28 +0800
From: Gedalya <gedalya@gedalya.net>
To: dovecot@dovecot.org
Cc: ??? <576709166@qq.com>
Subject: Re: mail_filter plugin: failed: EOF without input
Message-ID: <84fcd237-4290-2518-c4cf-486a049d9231@gedalya.net>
Content-Type: text/plain; charset=gb18030

On 2/7/20 4:33 PM, ??? wrote:
>
> cat?mail-filter-out.sh
> #!/bin/sh
> cat > tempfile
> cat ?mail-filter.sh
> #!/bin/sh
>
> USER=$1
> cat > tempfile
>
> Some important Error logs?
> Feb 07 15:49:19 lda(q1@a.com)<53648><rY6oIH8WPV6Q0QAA0J78UA>: Error: Mailbox INBOX: Saving mail: write(/home/a.com/q1/storage/m.1) failed: EOF without input
> Feb 07 15:49:19 lda(q1@a.com)<53648><rY6oIH8WPV6Q0QAA0J78UA>: Info: msgid=<77z2kkfmm1-7846bu3tx6@nsmail6.0>: save failed to INBOX: Mailbox INBOX: Saving mail: write(/home/a.com/q1/storage/m.1) failed: EOF without input
> Feb 07 15:49:19 lda(q1@a.com)<53648><rY6oIH8WPV6Q0QAA0J78UA>: Debug: auth-master: conn unix:/var/run/dovecot/auth-master (pid=10651,uid=0): Disconnected: Connection closed (fd=11)
>
Hi,

Your scripts are reading all the available input and not producing any output. This way the email message is lost.

You could add the line:

cat tempfile

or just replace "cat > tempfile" with "tee > tempfile"




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