CGI

Interface that allows scripts (programs) to run on a Web server  . CGI-scripts are used to put the content of a form into an email message, to perform a database query, to generate HTML  pages on-the-fly, etc. The most popular languages for CGI-scripts are Perl  and C  .

Common Gateway Interface is one of the most popular UNIX-based programs/devices that supply interfaces between browsers and servers on the Internet. A standard for running external programs from a World-Wide Web HTTP server. CGI specifies how to pass dynamic components to the executing program as part of the HTTP request. For example, it will allow answers typed into an HTML form on the client computer to be tabulated and stored in a database on the server-side computer. Commonly, the server-side CGI program will generate some HTML which will be passed back to the client's browser. For example, it might report to the client user that the form is not filled out properly or report the invoice total of an order. CGI allows the returned HTML (or other document type) to depend in any arbitrary way on the request. The CGI program can, for example, access information in a database and format the results as HTML. CGI is not a programming language. There are various "CGI" scripting programs. Perl is a common choice for writing CGI scripts. in UNIX code. Some HTTP servers require CGI programs to reside in a special directory, often "/cgi-bin" but better servers provide ways to distinguish CGI programs so they can be kept in the same directories as the HTML files to which they are related. In order to improve performance, Netscape devised NSAPI and Microsoft developed the ISAPI standard which allow CGI-like tasks to run as part of the host server process, thus avoiding the overhead of creating a new process to handle each CGI invocation.

(Common Gateway Interface) -- A set of rules that describe how a Web Server communicates with another piece of software on the same machine, and how the other piece of software (the “CGI program”) talks to the web server. Any piece of software can be a CGI program if it handles input and output according to the CGI standard.

Usually a CGI program is a small program that takes data from a web server and does something with it, like putting the content of a form into an e-mail message, or turning the data into a database query.

You can often see that a CGI program is being used by seeing “cgi-bin” in a URL, but not always.

See Also: cgi-bin , Web

CGI(Common Gateway Interface) A method used by www pages to communicate with programs run on the web server.CGI scripts enables you to use forms on your web site.

(Common Gateway Interface) A Web server scripting standard; a mechanism used to connect script to Web servers . In the past, most CGI programs were actually script files and were often written in scripting languages like PERL. Today, scripts can also be executable programs. You can write scripts in C and Visual Basic. The CGI specification has gone through several revisions. The best place to fine up-to-date information is the World Wide Web Consortium (W3) Web site (http://www.w3.org/ ).