Re: [Bashburn-info] cdrecord OPTIONS dump

[Steven W. O. <st...@sy...>]

On Wednesday, Oct 8th 2008 at 03:20 -0000, quoth Nick Warne:

=>On Tue, 7 Oct 2008 22:48:22 -0400 (EDT)
=>"Steven W. Orr" <st...@sy...> wrote:
=>
=>> 
=>> The reason is that that command writes to stderr and not to stdout.
=>> So, if you want your command to pipe its stderr to grep you have to
=>> say this:
=>> 
=>> cdrecord dev=/dev/<your_drive> driveropts=help -checkdrive 2>&1 | \
=>> 	grep -i Driver
=>> 
=>> which sez in English: "run the command and dup(2) stderr onto stdout
=>> and close stderr. Then take the combined stderr and stdout that is
=>> now on stdout and pipe it to grep."
=>> 
=>> Make sense?
=>
=>Yes, I think we all know about that... but it wasn't something I
=>thought about.
=>
=>Anyway, it still is peculair.  The line below NOW only prints out Driver
=>Options (I guess 20 lines will be enough) but still have to dump
=>to /dev/null.
=>
=>cdrecord dev=/dev/<you_drive> driveropts=help -checkdrive 2>&1
=>> /dev/null | grep -A 20 "Driver options"
=>
=>Please test this line - if it works for all of us, I guess it could be
=>used to only print out drivers options.

That works.

-- 
steveo at syslang dot net TMMP1 http://frambors.syslang.net/
Do you have neighbors who are not frambors? Steven W. Orr