Use of common Perl modules

A brief description of http://www.perldoc.com/perl5.6/pod/perlmodlib.html for some common modules

Use modules in Perl:
Module: http://www.cpan.org/modules/01modules.index.html
Installation module:
1. Perl makefile. pl
2. Make
3. Make Test
4. Make install
You can also run the following command to install the module (the applicable system RedHat 9.0 is known. I don't know about other systems. Please try again.
Perl-mcpan-e shell>

Enter: Install model_name

View the module help:
Perldoc model_name
For example:
Perldoc net: ftp

Existing modules: (the following content is transferred from CU. Thank you for your friends)
Note:
The following code is tested in FreeBSD & Solaris. The Perl version is 5.005_03.

(1) Net: ftp
(2) Net: Telnet
(3) lwp: simple, get ()
(4) Secondary CT
(5) XML: simple, xmlin ()
(6) data: dumper, dumper ()
(7) IO: Socket
(8) Date: manip, datec1c (), unixdate ()
(9) Date: manip, date_cmp ()
(10) file: Find, find ()
(11) extutils: installed, new (), modules (), version ()
(12) DBI, connect (), prepare (), execute (), fetchrow_array ()
(13) getopt: std
(14) proc: processtable
(15) Shell
(16) Time: hires, sleep (), time ()
(17) HTML: linkextor, links (), parse_file ()
(18) Net: Telnet, open (), print (), Getline ()
(19) compress: zlib, gzopen (), gzreadline (), gzclose ()
(20) Net: POP3, login (), list (), get ()
(21) Term: ansicolor
(22) Date: calc calendar (), today ()
(23) Term: CAP, tgetend (), tgoto, tputs ()
(24) HTTPD: Log: Filter
(25) Net: LDAP
(26) Net: SMTP mail (), to (), data (), datasend (), auth ()
(27) MIME: base64, encode_base64 (), decode_base64 ()
(28) Net: IMAP: simple, login (), mailboxes (), select (), get ()...
(29) Bio: DB: NOC, Bio: seqio
(30) Spreadsheet: parseexcel
(31) Text: csv_xs, parse (), fields (), error_input ()
(32) Benchmark

Note:
The code below is tested under RH linux7.2, And the Perl version is 5.6.0.

(33) http: daemon, accept (), get_request ()...
(34) array: Compare, compare (), full_compare ()...
(35) algorithm: diff, diff ()
(36) List: util, max (), min (), sum (), maxstr (), minstr ()...
(37) HTML: parser
(38) Mail: sender
(39) Time: hires, gettimeofday (), usleep ()
(40) image: magick

The following modules pass through RedHat 9.0 and Perl version v5.8.0 built.
(41) data: searchreplace
----------------------------------------------------------
(1) Net: ftp

#! /Usr/bin/perl-W
# File: ftp_recent.pl
# Figure 6.1: downloading a single file with net: ftp
Use Net: FTP;

Use constant host => 'ftp .perl.org ';
Use constant dir => '/pub/CPAN ';
Use constant file => 'recent ';

My $ FTP = net: ftp-> New (host) or die "couldn't connect :";
$ FTP-> login ('anonymous') or die $ FTP-> message;
$ FTP-> CWD (DIR) or die $ FTP-> message;
$ FTP-> get (File) or die $ FTP-> message;
$ FTP-> quit;

Warn "file retrieved successfully. \ n ";

-----------------------------------------------------------
(2) Net: Telnet
#! /Usr/bin/perl-W
# File: remoteps. pl

Use strict;
Use Net: Telnet;
Use constant host => 'phage .cshl.org ';
Use constant user => 'lstein ';
Use constant pass => 'xyting ';

My $ Telnet = net: telnet-> New (host );
$ Telnet-> login (user, pass );
My @ lines = $ telnet-> cmd ('ps-Ef ');
Print @ lines;

--------------------------------------------------------------
(3) lwp: simple, get ()
#! /Usr/bin/perl-W
Use strict;
Use lwp: simple QW (get );

My $ url = Shift | "http://www.chinaunix.net ";
My $ content = get ($ URL );

Print $ content;

Exit 0;
The simplest and most convenient way to get a webpage.

-------------------------------------------------------------
(4) Secondary CT

PHP code:

#! /Usr/bin/perl
Use strict;
Use reverse CT;

My $ timeout = 2;
My $ delay = 1;
My $ cmd = "ssh ";
My @ Params = QW/202.108.xx.xx-lusername-P22 /;
My $ pass = "passwd ";

My $ exp = benchmark CT-> spawn ($ cmd, @ Params) or die "can't spawn $ cmd \ n ";
$ Exp-> round CT ($ timeout,-Re => '[PP] assword :');
$ Exp-> send_slow ($ delay, "$ Pass \ r \ n ");

$ Exp-> interact ();
$ Exp-> hard_close ();

Exit 0;

-----------------------------------------------------------------
5) XML: simple, xmlin ()

PHP code:

#! /Usr/bin/perl-W
Use strict;
Use XML: simple;
My $ text = <XML;
<? XML version = "1.0 "? >
<Web-app>
<Servlet>
<Servlet-Name> php </servlet-Name>
<Servlet-class> net. php. servlet </servlet-class>
</Servlet>
<Servlet-mapping>
<Servlet-Name> php </servlet-Name>
<URL-pattern> *. php </url-pattern>
</Servlet-mapping>
</Web-app>
XML
My $ x = xmlin ($ text );
Foreach my $ tag (Keys % $ X)
{
My % H =%{$ $ X {$ tag }};
Foreach (Keys % H)
{
Print "$ tag => ";
Print "$ _ => $ H {$ _} \ n ";
}
}
Exit 0;

----------------------------------------------------------------
(6) data: dumper, dumper ()

PHP code:

#! /Usr/bin/perl-W
Use strict;
Use Data: dumper;

Print dumper (@ INC );
Print dumper (% env );
Exit 0;

-------------------------------------
(7) IO: Socket

PHP code:

#! /Usr/bin/perl-W
Use strict;
Use IO: socket;

My $ host = "www.chinaunix.net ";
My $ Port = "80 ";
My $ http_head = "Get/HTTP/1.0 \ nhost: $ HOST: $ port \ n ";
My $ sock = IO: Socket: iNet-> New ("$ HOST: $ port ")
Or die "socket () error, reason: $! \ N ";

Print $ sock $ http_head;
Print <$ sock>;

Exit 0;

---------------------------------------------------------------
(8) Date: manip, datec1c (), unixdate ()

PHP code:

#! /Usr/bin/perl
Use strict;
Use Date: manip;
My $ date1 = "Fri Jun 6 18:31:42 GMT 2003 ";
My $ date2 = "2003/05/06 ";
My $ flag = & date_cmp ($ date1, $ date2 );

If ($ flag <0)
{
Print "date1 is earlier! \ N ";
}
Elsif ($ flag = 0)
{
Print "the two dates are identical! \ N ";
}
Else
{
Print "date2 is earlier! \ N ";
}
Exit 0;

--------------------------------------------------------------------
10) file: Find, find ()
PHP code:

#! /Usr/bin/perl-W
Use strict;
Use File: Find;

My $ file = "access. log ";
My $ Path = "/";

Find (& process, $ PATH );

Sub process {print $ file: Find: Dir, "$ _ \ n" If (/$ FILE /);}

Exit 0;

# Search for objects in the Unix File tree structure.

---------------------------------------------------------------
(11) extutils: installed, new (), modules (), version ()

View the information of the installed modules.
PHP code:

#! /Usr/bin/perl
Use strict;
Use extutils: installed;

My $ inst = extutils: installed-> New ();
My @ modules = $ inst-> modules ();

Foreach (@ modules)
{
My $ ver = $ inst-> Version ($ _) | "??? ";
Printf ("%-12 s -- % s \ n", $ _, $ ver );
}
Exit 0;

--------------------------------------------------------------------
(12) DBI, connect (), prepare (), execute (), fetchrow_array ()

PHP code:

#! /Usr/bin/perl
Use strict;
Use dBi;

My $ DBH = DBI-> connect ("DBI: mysql: dbname", 'user', 'passwd ','')
Or die "can't connect! \ N ";
My $ SQL = QQ/show variables /;
My $ something = $ DBH-> prepare ($ SQL );
$ Something-> execute ();

While (my @ array = $ th-> fetchrow_array ())
{
Printf ("%-35 s", $ _) foreach (@ array );
Print "\ n ";
}
$ DBH-> disconnect ();
Exit 0;

------------------------------------------------------------------------
(13) getopt: std

Command Line Parameter Parsing.

PHP code:

#! /Usr/bin/perl
Use strict;
Use getopt: STD;

My % opts;
Getopts ("C: HV", % opts );

Foreach (Keys % opts)
{
/C/& print "Welcome to", $ opts {$ _} | "chinaunix ","! \ N ";
/H/& print "Usage: $0-[HV]-[c msg] \ n ";
/V/& print "this is demo, version 0.001.001 built for $ ^ O \ n ";
}
Exit 0;

------------------------------------------------------------------------
(14) proc: processtable

# Directly access the Unix Process Table, similar to ps command.

PHP code:

#! /Usr/bin/perl
Use strict;
Use proc: processtable;

My $ Pt = new proc: processtable;

Foreach (reverse sort @ {$ Pt-> table })
{
Print $ _-> PID, "=> ";
Print $ _-> cmndline, "\ n ";
}
Exit 0;

--------------------------------------------------------------------
(15) Shell

PHP code:

#! /Usr/bin/perl
Use strict;
Use shell;

Print "now is:", date ();
Print "current time is:", date ("+ % t ");

My @ dirs = ls ("-LAF ");
Foreach (@ dirs)
{
Print if (// $/); # print directory
}
Exit 0;

Shell commands are called directly as functions in Perl.

---------------------------------------------------------------------
Another use of time: hires module.

(16) Time: hires, sleep (), time ()

PHP code:

#! /Usr/bin/perl
Use strict;
Use Time: hires QW (sleep time );

$ | = 1;
My $ before = time;
For my $ I (1 .. 100)
{
Print "$ I \ n ";
Sleep (0.01 );
}
Printf ("time used: %. 5f seconds \ n", time-$ before );
Exit 0;

Use Time: hires, this module provides enhanced versions of sleep (), alarm (), time ()
Replace the built-in functions of Perl.
The sleep () and alarm () parameters can be decimal places. For example, sleep (0.1) indicates sleep for 0.1 seconds,
Time () can return floating point numbers.