Egrep ERE to find null

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05-02-2013

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The main thing is the "quotes".
Please run the script, enter a * and see what happens...

Code:

echo -n x

suppresses line feed
Therefore the escape with

Code:

echo x-n x

But actually not needed when quoted

Code:

echo "-n x"

You don't need back-ticks and count the output characters if you take the exit status from egrep, as in my example.

---------- Post updated at 04:14 PM ---------- Previous update was at 04:05 PM ----------

while ! can be written as until

Code:

until echo "$jobname" | egrep '^[^[:blank:]]+$' >/dev/null
do
...

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