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Extract variable name in a string

 
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# 1  
Old 12-12-2013
Extract variable name in a string
Hi,
I'm doing a script to list all scripts called by a "master" script.
But I have an issue as there is some variables in the name of the called scripts.

Example:
Code:
% cat master_script.sh
ENVIR=PROD
VERSION=1.2
/users/maturix/$ENVIR/program_$VERSION.sh

I would like my script displays a kind of grep "\.sh" master_script.sh but by replacing the variables by their content, to have such output:
Code:
/users/maturix/PROD/program_1.2.sh

Note that the variables are not only these ones ENVIR & VERSION.

I did something like that to modify the variable between two /:
Code:
var=$(grep "\.sh" master_script.sh | sed 's/\//\n/g' | grep '^\$')
var_content=$(grep "^$(echo $var | cut -c 2-100)=" master_script.sh | cut -d'=' -f2)
grep "\.sh" master_script.sh | sed "s/$var/$var_content/g"

Which give as result:
/users/maturix/PROD/program_$VERSION.sh

Now I need to change $VERSION with its content, and more generally I will have other cases, not only variable between // or before a "."
Is there a generic way to extract the variable names from a string ?
Last edited by maturix; 12-12-2013 at 09:37 AM..
# 2  
Old 12-12-2013
hi ur explantion is bit confusing

did u try using double quotes
Code:
" "

# 3  
Old 12-12-2013
My question is how from a text get the variable declare in it.
I success to do it if the variable is between two slash /.
My problem now is to do it whatever the caracters before and after.

How to get the word starting by a $ ?

(I've updated my question to make it clearer I hope).
Last edited by maturix; 12-12-2013 at 09:38 AM..
# 4  
Old 12-12-2013
does this answer your question

Code:
user010@sshell ~ $ cat new.sh
ENVIR=PROD VERSION=1.2
#/users/maturix/$ENVIR/program_$VERSION.sh
echo "/users/maturix/$ENVIR/program_$VERSION.sh"
user010@sshell ~ $ ./new.sh
/users/maturix/PROD/program_1.2.sh

# 5  
Old 12-12-2013
no I don't want to modify the master_script (which is used in my prod).
I need to do a new script which read master_script.sh and which displays all the scripts called by it.
# 6  
Old 12-12-2013
Take a look at what you have written...
Code:
/users/maturix/PROD/program_$VERSION.sh

Code:
ENVIR=PROD
VERSION=1.2

Now PROD is a _value_ of variable ENVIR, and, ($)VERSION is a variable itself...

Are you after the _values_, the variable names, or, a combination of both?

I suspect you want the _values_:-
PROD
...and...
1.2
...but I could be wrong...
# 7  
Old 12-12-2013
At the end I want the text with the value instead of the variable, i.e. :
/users/maturix/PROD/program_1.2.sh

But if I can get the variable name in a first step, then I know how to retrieve the variable value and replace the name by the value.
 
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