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# 1  
Old 04-23-2008
grep
is it possible to direct grep statement to a variable rather than a file
example:

grep -w [a-z] check > check1

can the "check1" be a variable?
because i want to use it to test a condition where check1 is empty
example

if [ "$check1" = " " ]

thanks
# 2  
Old 04-23-2008
You can do that, but probably it's better to note that grep already sets its return code to indicate whether or not it successfully found anything.

Code:
if grep -w '[a-z]' check; then
  echo 'previous line(s) matched'
else
  echo no match
fi

The syntax for capturing the output of a command (into a variable, for example) is to use backticks. These are grave accents (ASCII 96), not regular apostrophes.

Code:
variable=`command whose output you want to capture`

# 3  
Old 04-23-2008
Hi,

U can use

check1=grep -w [a-z] check

But take care of multiple return values from grep

Thanks
--Penchal
# 4  
Old 04-23-2008
Infact it should be

check1=`grep -w [a-z] check`

-- penchal
# 5  
Old 04-23-2008
(Never mind, posting clash)
# 6  
Old 04-23-2008
thanks
both of the solution do works
thanks for the help
i now understand more about grep command
 
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