Redirect hdparm output to grep?

[Michele Sanges]

Il giorno mar, 13/05/2008 alle 22.48 -0700, Alan Dayley ha scritto:

> In a shell script I want to do something based on the presence or not
> of a USB mounted partition.  hdparm can indirectly report this
> information with a partition rescan like this:
> 
> hdparm -z /dev/sda
> 
> I want to then parse the output of this command to determine if a
> partition was found or not.  My proposed command is:
> 
> /bin/hdparm -z /dev/sda | grep -c sda1
> 
> This should return a count of the string "sda1" in the output from
> hdparm,  But, it does not work.  First it appears that most of the
> hdparm output goes to stderr instead of stdout.  Secondly the various
> piping combinations I have tried don't produce output to grep.
> 
> Below are examples of what I have tried, exposing my shell scripting
> ignorance.  Note that the command lines with a pipe to grep end with a
> "0" which is grep's contribution to the output.  It is always "0" even
> if the sought text is present.  The attempted pipes to a file are even
> worse syntax, I'm sure.
> 
> This question is not necessarily a Busybox issue even though both
> hdparm and grep in use here are from Busybox.  I may just not have the
> shell scripting chops to know the right syntax.  Anyone have any
> thoughts or education to give me?
> 
> Alan

Maybe I have not understood but do you want see if the device /dev/sda1
is mounted somewhere?

What about:

	mount | grep sda1

Regards.

Michele