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I have a bash shell script which has a variable $DEVICE. Now I would like to use "grep" to do some pattern matching on the contents of variable $DEVICE.
For example, suppose variable DEVICE has "ABC XYZ" stored in it. Now I would like to grep "ABC" on $DEVICE.
I am not ale to figure out how to do it. It is easy to do a grep on file:
grep "ABC" <file-name> but how do you do on a variable?
You can't get value from $DEVICE using grep. You can extract contents of assignment operation using something like
grep "^\$DEVICE[ \t]*=[ \t]*.*$" file.txt| sed 's/^\$DEVICE[ \t]*=[ \t]\(.*\.)$/\1/g'
(grep finds line with assignment, sed cuts off left part of assignment. Probably can be made 2x times shorter)
But you can't extract value from script without running it, because if there are operations that change value of $DEVICE later, grep/sed won't handle it, and you will get incorrect result.
, no it was Greppo, I hid the answer here (& in my OP) in a background matching color tag -- highlight it to read it; or did you know that?
... Of course you knew that, quoting the post displayed the hidden answer & the method of hiding it.
Last edited by archtoad6; 02-04-2009 at 06:20 AM.
Reason: fix color tag