🚀 go-pugleaf

When mush incorporates newly arrived mail into the temporary
file, I've noticed that it occasionally truncates the new message.
The system mailbox is ok, but the file in $tmpdir is damaged.

For example, the last message in /tmp/.mush.624588 currently
looks like:

	From daemon Tue Aug 22 15:09:48 1989
	Posted-Date: Tue, 22 Aug 89 15:09:37 CDT
	Received-Date: Tue, 22 Aug 89 15:09:38 CDT
	Message-Id: <8908222009.AA10202@cs.utexas.edu>
	Received: by cs.utexas.Received: by cs.utexas.

There is no trailing newline on the obviously mangled last line
of the file.  For reference, my system folder, ~/mailbox has headers
in tact:

	From daemon Tue Aug 22 15:09:48 1989
	Posted-Date: Tue, 22 Aug 89 15:09:37 CDT
	Received-Date: Tue, 22 Aug 89 15:09:38 CDT
	Message-Id: <8908222009.AA10202@cs.utexas.edu>
	Received: by cs.utexas.edu (5.59/1.39)
		id AA10202; Tue, 22 Aug 89 15:09:38 CDT
	Date: Tue, 22 Aug 89 15:09:37 CDT
	X-Mailer: Mail User's Shell (6.5 4/17/89)
	From: daemon@cs.utexas.edu (The devil himself)
	To: daemon@cs.utexas.edu
	Subject: Error spooling ehandler.ps to -Plw1

	<body of message deleted>

I #define DOT_LOCK and HOMEMAIL.
I "set tmpdir=/tmp".
It happens with 6.5.6, though I've seen it as far back as 6.5.1.
This seems to happen only when the system folder gets large,
i.e. 300 messages with 500K data.  It's not reproducible.

Anybody else seen it?

Fletcher