Shell Programming and Scripting

I have a config file that needs to be formatted before it's sourced to a script. I've been formatting it with sed and dropping it in /tmp then sourcing it from there.

I'd like to just format the config file with sed then declare the variables without having to create a temporary file in /tmp. So I tried a loop like this ...

Code:

for line in $config_formatted; do
  var_name=$(echo "$line" | awk -F= '{print $1}')
  var_value=$(echo "$line" | awk -F= '{print $2}' | sed 's/\(^"\|"$\)//g')
  declare $var_name=$var_value
done

This works fine except when $var_value contains a value that appends itself with another variable that should have been declared already. For example, when it formats my config file and runs through the loop I have it echo a few variables it declared at the end. I end up with ...

Code:

$ ./configRead

audit_host : http://server
non_ie_page : ${audit_host}/oa/admin_pc_add_2.php

As you can see from my original loop, I used sed to format $var_value to remove the quotations...which seems a little odd to have to do in the first place. So perhaps I don't fully understand how declare is working? Is this simply a limitation that I cannot get around?

Thanks in advance for any advice.

What is the format of the config file? Why do you have to change it?

Why are you using declare? It's not necessary.

It is odd. Why do it?

What do you think it does?

I don't know of any limitation to declare. It does what it is supposed to (but I've never had a reason to use it).

The config file was mostly intended to be used with a vb script. I didn't really want to start maintaining two separate config files, as I actually do use the vb script as well.

The config file holds variables in the form of ...

variable = "value"

I'm using declare because if I don't bash will try to use $var_name as a command. Using declare I can create variables by using variables. This way I can just add variables to the config file if needed and I don't need to go back to the script and manually declare each one separately on it's own line.

Because they would throw my script off as the script takes some action based on the contents of the variables. I would have to account for the variable values having quotations around them which they shouldn't have in the first place.

Well, running 'help declare' at the shell gives me ...

I assumed (yeah,yeah...bad idea to make assumptions ) that it would be like declaring a variable normally only with this the declaration is explicit and you can define its type (dunno exactly what practical use that would give?).

However, after I wrote this I wrote a test that simply does...

Code:

#!/bin/bash

audit_host="http://server"
var_name="non_ie_page"
var_value="${audit_host}/oa/admin_pc_add_2.php"
declare $var_name=$var_value

echo "audit_host : $audit_host"
echo "non_ie_page : $non_ie_page"

and it gives the following output ...

So I'm guessing the issue ultimately lies in the way I'm getting the variable values, which seems to allude to a pipeline "issue" (not really an issue, just the way bash handles it) that I read in this thread.

However, I just got around my problem by doing the following ...

Code:

    for line in $config_formatted; do
      var_name=$(echo "$line" | awk -F= '{print $1}')
      var_value=$(echo "$line" | awk -F= '{print $2}' | sed 's/\(^"\|"$\)//g')
      echo "$line" | grep -q '^.*_page=\$' && var_value="${audit_host}${var_value/\$\{audit_host\}/}"
      declare $var_name=$var_value
    done

So all in all, it works now. It's a bit of a kluge, but oh well.

Thanks for your reply!