[ECOS] blocking read of serial device driver

[ECOS] blocking read of serial device driver

[Roland Caßebohm]

Hi,

I like to have a blocking read with termios for th serial device driver. I 
think when I set c_cc[ VMIN ]=1 it should block, but it doesn't. I have 
looked at the code of termios_read(). The function can only block in 
canonical mode. But when I set c_cc[ VMIN ]=1 the function have to block 
since at least 1 character is received.
My complete configuration:

	newtio.c_cflag = B38400 | CS8 | CLOCAL | CREAD;
	newtio.c_iflag = IGNPAR;
	newtio.c_oflag = 0;
	newtio.c_lflag = 0;
	newtio.c_cc[VTIME] = 0; // inter character timer unused
	newtio.c_cc[VMIN] = 1;  // blocking read until 1 chars received

Roland
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___________________________________________________

VS Vision Systems GmbH, Industrial Image Processing
Roland Caßebohm
Aspelohe 27A, D-22848 Norderstedt, Germany
Mail: roland.cassebohm@visionsystems.de
http://www.visionsystems.de
___________________________________________________

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Re: [ECOS] blocking read of serial device driver

[Jonathan Larmour]

Roland Caßebohm wrote:
> 
> Hi,
> 
> I like to have a blocking read with termios for th serial device driver. I
> think when I set c_cc[ VMIN ]=1 it should block, but it doesn't. I have
> looked at the code of termios_read(). The function can only block in
> canonical mode. But when I set c_cc[ VMIN ]=1 the function have to block
> since at least 1 character is received.

As per
http://sources.redhat.com/ecos/docs-latest/ecos-elix/ecos-elix.2.html#pgfId=2626807
we only support MIN=0,TIME=0 at present.

Look at http://people.freebsd.org/~luoqi/ecos/vtime.diff for some
improvements, but we never got a copyright assignment :-|.

Jifl
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