Hi,
I'm trying to write a script that will put a network interface down/up using ifconfig so that the mac address can be changed. The script will prompt the user to choose a interface, i.e (etc0,etc1,etc...) then, ask if the new mac address will be random, or one chosen by the user.

The problem is that I get an error when trying to execute ifconfig from the system function. Because the interface is selected from user input, I write the system function as system("ifconfig $device down");. If I remove down, there is no error. If I remove the variable $device and put eth0, there is no error. If I set the variable $device to eth0 above the system function, there is no error. Here is part of the script

###   Test if a device has been selected   ####
if ($device eq "")
{
print "Please Choose a device\n";
system ("ifconfig");
print "Choice: "; 
$device = <>;
}                       
else
{ 
###   Display Change Mac Address Menu   ###
print "1.  Create Random new Mac Address for device $device\n";
print "2.  Create a Specefic New Mac Address for device $device\n";
print "3.  Go Back to MAIN MENU\n\n";
print "Choice: ";
$choice = <>;
            
if ($choice == "1")
{
###   Create Random New MacAddress   ###
system("ifconfig $device down");
system("macchanger -r $device");
system("ifconfig $device up");
}

[download]

When the system function is executed it will do a ifconfig eth0 (if eth0 is what the user choose), then on a new line say: sh: line 1: down command not found.
Any ideas as to what could be causing this error? and how I can fix it?
Thanks in advance.

In reply to perl system function by ironside

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