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[Stuart Sears]

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Dan Track wrote:
> Hi
> 
> Simple question, I'm running a command `command`, what I'd like to do
> is check to see if the response is empty then exit. Does anyone know
> how I can perform that check?

by empty, I presume you mean 'prints nothing to stdout' ?
 - you can test the length of a string like this:
(man test)

if [ -z "$(grep foo /boot/grub/grub.conf)" ] ; then
  echo "response is empty"
  exit 1
else
  echo "response was not empty"
fi

or do you mean 'command does not work'
you can test for a non-zero return code like this:

if [ $(grep 'foo' /boot/grub/grub.conf) ]; then
  echo "yes"
else
  echo "no"
fi


the two tests are similar but not identical

$(command) is exactly the same as `command`

any use?

Stuart

- --
Stuart Sears RHCA RHCX
To err is human, to forgive is Not Company Policy.
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