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From: stevens@hsi.UUCP (Richard Stevens)
Newsgroups: comp.sys.att
Subject: Re: cu on a 3b1 is SLOW
Summary: read, write system calls of 1 byte
Message-ID: <540@hsi86.hsi.UUCP>
Date: 30 Jul 89 10:43:19 GMT
References: <18818@mimsy.UUCP>
Distribution: usa
Organization: Health Systems Intl., New Haven, CT
Lines: 21

In article <18818@mimsy.UUCP>, steveg@tove.umd.edu (Steve Green) writes:
> 
>  I am a new unixpc user, but it seems that when I do a cu to another unix
>  machine at 9600 baud (a Mac II) it moves like molasses.

The first problem is that cu does a read() system call of 1 byte from
the communications line, followed by a write() of 1 byte to the standard
output.  This loop is the heart of cu, and it is slow as molasses on the 3b1.
There's no way around this, unless you have the source to a cu.
You should run some other terminal emulator instead (assuming there
is one that doesn't have this basic limitation).

The second problem is that the 3b1 console can't run at 9600.
Cat a big file to the screen and time it - it's about 5500 baud max.
I'd guess this is due to the implementation of the ansi driver for the
console, as I've heard that an attached terminal can indeed run at 9600.

	Richard Stevens
	Health Systems International, New Haven, CT
	   stevens@hsi.com
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