Can I use ECHO to execute commands?

Question

I've come up with a cool script that will produce the output that I need, but it only displays on the screen, so I have to copy, then paste in the commands to get them to execute. Here's the abbreviated version of my script:

#!/bin/bash
runc=/etc/csf/csf.pl -d
for IP in `tail -400 iptext.txt`
do
cc=`geoiplookup $IP`
echo -e $runc $IP    $cc | grep Algeria
echo -e $runc $IP    $cc | grep Argentina
echo -e $runc $IP    $cc | grep Armenia
echo -e $runc $IP    $cc | grep Azerbaijan
echo -e $runc $IP    $cc | grep Bolivia
echo -e $runc $IP    $cc | grep Brazil
done

Okay, so it loops through the list of IP addresses in iptext.txt, then does a geoIP lookup on each, if (in this example) there are two geoIP matches in the list, let's say for Armenia and Brazil, I will see output like this to the shell window:

/etc/csf/csf.pl -d 46.162.242.17 GeoIP Country Edition: AM, Armenia
/etc/csf/csf.pl -d 200.147.38.50 GeoIP Country Edition: BR, Brazil

This is great, but I want more than just output, I actually want the /etc/csf/csf.pl -d command to run, and block (just and only) the IP in the lines that match the country name, in the list.

I've tried various things with my limited knowledge of shell scripting, but so far, nothing seems to work. So is there some option for ECHO I am missing that would actually run the command rather than just printing out the line?

Solution 1

Just put your command into parenthesis like this:

echo $(ls)

You can also have text before the command

echo "The date is $(date)"

For Example

echo "Enter Text Here $(Command Here)"

Solution 2

A simple way that won't need modification of your script would be to pipe the command's output to another bash instance. Like this:

yourscript | bash -

The - tells bash that it should read commands from stdin.

---

However, if you are not searching for a quick solution, it is possible to build and execute the command dynamically as well. Like this:

cmd="ls"
if [ "foo" != "bar" ] ; then
    cmd="$cmd -a"
then

# ... and so on

# now execute it:
$cmd

Solution 3

You can use eval to execute a string:

eval $cmdstring

Solution 4

There is a bash builtin eval, this executes commands like they were typed in at your shell. For example within your script you can do the following:

eval $(echo -e $runc $IP    $cc | grep Algeria)

This will process your echo in a subshell and the output will be executed like you typed it in your shell followed by enter.

See below exerpt from bash manual:

eval [arg ...] The args are read and concatenated together into a single command. This command is then read and executed by the shell, and its exit status is returned as the value of eval. If there are no args, or only null arguments, eval returns 0.

Solution 5

echo `pwd`

above command works for me.

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