i made a guestbook and i want to add some function. eg:del post and modify post i can do the del function , but don't know how to do the modify, below is my admin.pl 
#!/usr/bin/perl

print "content-type:text/html\n\n";

$admin ="sonic";

if($ENV{'REQUEST_METHOD'} eq "POST"){
read(STDIN,$buffer,$ENV{'CONTENT_LENGTH'});
}else{
$buffer=$ENV{'QUERY_STRING'};
}

@pairs=split(/&/,$buffer);
foreach $pair(@pairs){
($name,$value)=split(/=/,$pair);
$value=~tr/+/ /;
$value=~s/%([0-9a-fA-F][0-9a-fA-F])/pack("C",hex($1))/eg;
$value=~s/</&lt;/g;
$value=~s/\n/<br>/g;
$FORM{$name}=$value;
}

open(READ,"guestbook.dat");
@lines=<READ>;
close(READ);

my $pw = $FORM{'password'};
my $adminmsg = $FORM{'ownermsg'};
my $modnum = $FORM{'postid'};

if ( $admin eq $pw ) {

foreach $line(@lines) {
( $number,$sign_name,$sign_email,$sign_homepage,$sign_icon,$sign_time,
+$sign_msg ) = split ( /__/, $line ) ;
if ( $modnum ne $number ) 
    {
push ( @data , $line );
open(WRITE,">guestbook.dat");
print WRITE @data;
close(WRITE);
    }
}
print "Loading ...";
print "<META HTTP-EQUIV=Refresh CONTENT=2;URL=viewguestbook.pl?action=
+view_post&start=0&end=$show>";
}else{
print <<EOF;
<center>wrong password<br>
Please <a href=javascript:window.history.back()>go back</a> !
</center>
EOF
}

[download]
if i want modify a post message($sign_message)only,
then write back into guestbook.dat ,
how to write back to the orginal place ,
is it use sort and resever ?
hope someone can understand my question!!

In reply to how can i modify the array ? by 12monkey

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