From mboxrd@z Thu Jan  1 00:00:00 1970
From: daniel.baluta@gmail.com (Daniel Baluta)
Date: Mon, 9 May 2011 15:08:34 +0300
Subject: char driver error
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OK. See how write and read works.

> $strace echo -n "abcd" > /dev/memory(/home/aravind/me
> write(1, "abcd", 4) ? ? ? ? ? ? ? ? ? ? = 1
> write(1, "bcd", 3) ? ? ? ? ? ? ? ? ? ? ?= 1
> write(1, "cd", 2) ? ? ? ? ? ? ? ? ? ? ? = 1
> write(1, "d", 1) ? ? ? ? ? ? ? ? ? ? ? ?= 1

>$ strace cat /dev/memory(/home/aravind/memory)

> read(3, "d", 32768) ? ? ? ? ? ? ? ? ? ? = 1
> write(1, "d", 1d) ? ? ? ? ? ? ? ? ? ? ? ?= 1

Please allocate space for more than 1 char, and also
correct memory_write

  tmp=buf+count-1; -> tmp=buf+*f_ps-1;

thanks,
Daniel.