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regular expression

Postfix Flush the Mail Queue

Traditionally you use the "sendmail -q" command to flush mail queue under Sendmail MTA. Under Postfix MTA, just enter the following command to flush the mail queue:
# postfix flush
OR
# postfix -f

To see mail queue, enter:
# mailq

To remove all mail from the queue, enter:
# postsuper -d ALL

To remove all mails in the deferred queue, enter:
# postsuper -d ALL deferred

postfix-delete.pl script

Following script deletes all mail from the mailq which matches the regular expression specified as the first argument (Credit: ??? - I found it on old good newsgroup)

#!/usr/bin/perl
 
$REGEXP = shift || die "no email-adress given (regexp-style, e.g. bl.*\@yahoo.com)!";
 
@data = qx</usr/sbin/postqueue -p>;
for (@data) {
  if (/^(\w+)(\*|\!)?\s/) {
     $queue_id = $1;
  }
  if($queue_id) {
    if (/$REGEXP/i) {
      $Q{$queue_id} = 1;
      $queue_id = "";
    }
  }
}
 
#open(POSTSUPER,"|cat") || die "couldn't open postsuper" ;
open(POSTSUPER,"|postsuper -d -") || die "couldn't open postsuper" ;
 
foreach (keys %Q) {
  print POSTSUPER "$_\n";
};
close(POSTSUPER);
 

For example, delete all queued messages from or to the domain called fackspamdomain.com, enter:
./postfix-delete.pl fackspamdomain.com
Delete all queued messages that contain the word "xyz" in the e-mail address:
./postfix-delete.pl xyz

Updated for accuracy.

Lighttpd restrict or deny access by IP address

Lighttpd logo

So how do you restrict or deny access by IP address using Lighttpd web server?

Lighttpd has mod_access module. The access module is used to deny access to files with given trailing path names. You need to combine this with remoteip conditional configuration. Syntax is as follows:

$HTTP["remoteip"] == "IP" : Match on the remote IP
$HTTP["remoteip"] !~ "IP1|IP2" : Do not match on the remote IP (perl style regular expression not match)
$HTTP["remoteip"] =~ "IP1|IP2" : Match on the remote IP (perl style regular expression match)

Task: Match on the remote IP

For example block access to http://theos.in/stats/ url if IP address is NOT 192.168.1.5 and 192.168.1.10 (restrict access to these 2 IPs only):

Open /etc/lighttpd/lighttpd.conf file
# vi /etc/lighttpd/lighttpd.conf
Append following configuration directive:

$HTTP["remoteip"] !~ "200.19.1.5|210.45.2.7" {
    $HTTP["url"] =~ "^/stats/" {
      url.access-deny = ( "" )
    }
 }

Save and restart lighttpd:
# /etc/init.d/lighttpd restart

Task: Block single remote IP

Do not allow IP address 202.54.1.1 to access our site:

$HTTP["remoteip"] == "202.54.1.1" {
       url.access-deny = ( "" )
  }

Do not allow IP address 202.54.1.1,202.54.2.5 to access our site:
Do not allow IP address 202.54.1.1 to access our site:

$HTTP["remoteip"] =~ "202.54.1.1|202.54.2.5" {
       url.access-deny = ( "" )
  }

See also

=> Lighttpd deny access to certain files

Howto: Linux Rename Multiple Files At a Shell Prompt

From my mailbag:

How do I rename multiple files at a shell prompt under Linux or UNIX operating systems?

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The replace command is a string-replacement utility. It changes strings in place in files or on the standard input. This command uses a finite state machine to match longer strings first. It can be used to swap strings. This command is similar to the Perl -pie syntax or sed (stream editor) command.
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