Re: Perl die after executing external program

[mr_mischief]

Backticks don't capture STDERR. You'd need to redirect STDERR on top of STDOUT for lftp as lftp uses STDERR for much of its interface.

Try this:

my $CLIENT = "lftp";
my $connectionString =  "" . $CLIENT . " -d -f script.ftp 2>&1";
my $result = `$connectionString` or die "\nERROR running $CLIENT: $!";
return $result;

I make no guarantees, but I did install lftp just to test this theory and look at this which shows STDERR being used:

[chris@pineapple ss64]$ >bar
[chris@pineapple ss64]$ lftp -d -f foo > bar
---- Resolving host address...
---- 1 address found: 64.131.79.110
Password:
[chris@pineapple ss64]$ cat bar
[chris@pineapple ss64]$ lftp -d -f foo > bar 2>&1
Password:
[chris@pineapple ss64]$ cat bar
---- Resolving host address...
---- 1 address found: 64.131.79.110
[chris@pineapple ss64]$

As a side note, I hope you're using SFTP or HTTPS (both of which modern versions of lftp support) if you're not using an anonymous connection. I don't use plain-text FTP with authenticated accounts, and I recommend others don't. Without getting into too many specifics about statistics, let's say it's common in the security department of a web hosting company to deal with customers whose hosting account credentials were stolen by malware or sniffing. It may be a small portion of customers who ever have a breach, but compromised passwords are a fairly common sort of breach. Use SFTP or scp if you can, and use HTTPS when possible if logging into a web app you actually care a lot about.

BTW, none of this is really Perl-specific beyond 'Backticks don't capture STDERR.'. Then again, those backticks are reminiscent of shell backticks which work the same way, so that's not even that Perl-specific.