This is our first CGI Perl example a href httpwwwcsucpeducgi binreplypl Click

This is our first cgi perl example a href

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This is our first CGI-Perl example <a href = ""> Click here to run the CGI program, reply.pl </a> </body> </html> - The connection from a CGI program back to the requesting browser is through standard output, usually through the server - The HTTP header needs only the content type, followed by a blank line, as is created with: print "Content-type: text/html \n\n"; #!/usr/local/bin/perl # reply.pl – a CGI program that returns a # greeting to the user print "Content-type: text/html \n\n", "<html> <head> \n", "<title> reply.pl example </title>", " </head> \n", "<body> \n", "<h1> Greetings from your Web server!", " </h1> \n </body> </html> \n"; Query string format
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Programming the WEB 10CS73 DEPT. OF CSE, SJBIT Page 152 In World Wide Web , a query string is the part of a Uniform Resource Locator (URL) that contains data to be passed to web applications such as CGI programs. The Mozilla URL location bar showing an URL with the query string title=Main_page&action=raw When a web page is requested via the Hypertext Transfer Protocol , the server locates a file in its file system based on the requested URL . This file may be a regular file or a program. In the second case, the server may (depending on its configuration) run the program, sending its output as the required page. The query string is a part of the URL which is passed to the program. Its use permits data to be passed from the HTTP client (often a web browser ) to the program which generates the web page. Structure A typical URL containing a query string is as follows: When a server receives a request for such a page, it runs a program (if configured to do so), passing the query_string unchanged to the program. The question mark is used as a separator and is not part of the query string. A link in a web page may have a URL that contains a query string. However, the main use of query strings is to contain the content of an HTML form, also known as web form . In particular, when a form containing the fields field 1 , field 2 , field 3 is submitted, the content of the fields is encoded as a query string as follows: field 1 =value 1 &field 2 =value 2 &field 3 =value 3 ... The query string is composed of a series of field-value pairs. The field-value pairs are each separated by an equal sign . The series of pairs is separated by the ampersand , '&' or semicolon , ';'. For each field of the form, the query string contains a pair field=value. Web forms may include fields that are not visible to the user; these fields are included in the query string when the form is submitted This convention is a W3C recommendation. W3C recommends that all web servers support semicolon separators in the place of ampersand separators.
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Programming the WEB 10CS73 DEPT. OF CSE, SJBIT Page 153 Technically, the form content is only encoded as a query string when the form submission method is GET . The same encoding is used by default when the submission method is POST , but the result is not sent as a query string, that is, is not added to the action URL of the form. Rather, the string is sent as the body of the request.
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