I've found some documentation on using the perl -s switch to get variables from the command line, but that's not really what I want. I'd like to take a command line argument that is a string that includes a command and a variable in the Perl script to print.

#!/usr/bin/perl

use strict;

my $host = 'localhost';

# Use 1 of the following lines:
#my $output = eval($ARGV[0]);
my $output = $ARGV[0];

print "COMMAND:  $output\n";
system($output);

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Now call with:

script.pl "echo hello"

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Output is:

{C} > script.pl "echo hello"
COMMAND:  echo hello
hello

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However, try:

{C} > test "echo $host"
COMMAND:  echo $host
$host

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I'd like "$host" that is printed to actually be "localhost" as is set in the script (my $host = 'localhost';) that is output. I had a feeling the "eval" would be needed, but that only works when the argument passed is the variable itself (ie: "$host", not "echo $host" and I need it to be the later since I'd like to pass more complex commands other than just 'echo').

In reply to Command Line Arg contains Variable and more by VinsWorldcom

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