安装DBD::mysql模块时
Perl: 5.8.6
shell> perl -MCPAN -e shell
cpan> install DBI
................
cpan> install DBD::mysql
提示错误信息，like this:
......
CPAN.pm: Going to build C/CA/CAPTTOFU/DBD-mysql-4.005.tar.gz

Can't exec "mysql_config": No such file or directory at Makefile.PL line 76.

Cannot find the file 'mysql_config'! Your execution PATH doesn't seem
not contain the path to mysql_config. Resorting to guessed values!
Can't exec "mysql_config": No such file or directory at Makefile.PL line 466.
Can't exec "mysql_config": No such file or directory at Makefile.PL line 466.
Can't exec "mysql_config": No such file or directory at Makefile.PL line 466.
Can't exec "mysql_config": No such file or directory at Makefile.PL line 466.
Can't exec "mysql_config": No such file or directory at Makefile.PL line 466.
Can't exec "mysql_config": No such file or directory at Makefile.PL line 466.
Failed to determine directory of mysql.h. Use

perl Makefile.PL --cflags=-I<dir>
to set this directory. For details see the INSTALL.html file,
section "C Compiler flags" or type

perl Makefile.PL --help

#aptitude install libmysql++-dev  libmysql++2c2a

use Encode qw(from_to);
$string="北京";
from_to($string, "utf8", "GB2312");    #需要你自己根据编码改一下
$string=~s/(\W)/sprintf("%%%02X",unpack("C",$1))/eg;
print $string;

my $path = `cwd`;

#!/usr/bin/perl
use Net::SMTP;

my $mailhost = "smtp.163.com"; # the smtp host
my $mailfrom = 'notfour@163.com'; # your email address
my @mailto = ('fayland@gmail.com', 'not_four@hotmail.com'); # the recipient list
my $subject = "此为标题";
my $text = "此为正文\n第二行位于此。";

$smtp = Net::SMTP->new($mailhost, Hello => 'localhost', Timeout => 120, Debug => 1);

# anth login, type your user name and password here
$smtp->auth('user','pass');

foreach my $mailto (@mailto) {
    # Send the From and Recipient for the mail servers that require it
    $smtp->mail($mailfrom);
    $smtp->to($mailto);

    # Start the mail
    $smtp->data();

    # Send the header
    $smtp->datasend("To: $mailto\n");
    $smtp->datasend("From: $mailfrom\n");
    $smtp->datasend("Subject: $subject\n");
    $smtp->datasend("\n");

    # Send the message
    $smtp->datasend("$text\n\n");

    # Send the termination string
    $smtp->dataend();
}
$smtp->quit;