CGIs

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CGIs

• Server-Side Programming

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What is a CGI?

• CGI -gt Common Gateway Interface - a way for web
  pages to access computer programs stored and
  running (key concept!!!) on a web server.
• PPBHS uses CGIs in Dashboard Page..
• CGI Programs mainly used for Form Validation,
  E-Commerce, Guest Books, etc...

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CGIs

• CGI programs can be written in any programming
  language most written with ASP (Active Server
  Pages - Server-Side JS - Dashboard page - ASP
  only works on UNIX Web Servers), C, or PERL
• Two Major Types of Web Servers UNIX (Apache)
  Servers and MS IIS (ASP).

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CGIs

• We will first learn PERL since we need for the
  commercial sites we are developing -- -gt onednr
  servers -- -gt OCPO, FVINCENT, LENNYSMARKET, and
  TRIC are hosted -gt UNIX Apache Servers.
• We need Guest Book CGI for FV Bulletin Board for
  OCPO, etc.

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PERL

• PERL - Practical Extraction and Report Language -
  high-level, interpreted lang. - not even designed
  for use with web (more info can be found at
  http//www.perl.com) created in 1986 to easily
  create reports
• PERL is easily ported from OS to another (because
  it is interpreted)

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PERL

• Has a rep for being a cool lang
• and for being fun most of you guys know JS so it
  will be fairly easy for you guys to pick up..

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PERL

• How is PERL called out from a HTML
• Heres is how you via a form
• ltFORM METHODpost ACTIONhttp//www.lennysmarket.
  com/cgi-bin/bulletin.cgigt
• Most CGI programs are stored in a directory
  called cgi-bin.

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PERL Data

• 3 5 (result is 8)
• 3 cream (result is 3)
• ice cream (result 0)
• ice . cream (result icecream -gt
  concatenation)

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PERL Data

• print 3 Main Street (print is the Perl
  function to print back to web page 3 Main
  Street is a constant)
• variables
• address3 Main Street
• print address
• sum3 5

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Perl Data

• Print what is up\ndont know
• produces what is up
• dont know
• print you won prize

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Creating a PERL CGI Script

• Using NotePad/WordPad/Word - simple text editor..
• Code Perl Program
• Save as text-only file with extension cgi
• e.g., nick.cgi.
• Save in servers CGI-BIN Directory