CGI

Common Gateway Interface

Back-end, web server, technology.

Learn, Guides,...
Libraries with scripts
- www.cgi-resources.com/
See also HTTP error codes when a CGI fail to execute appropriately
Examples (< may fail depending on server config - if dir listing is allowed or not) (all direct links below opens in a sep. window/tab):
- printenv, - no extension
- printenv.bat
- printenv.cgi
- printenv.exe
- printenv.pl
- printenv.pl.txt
- printenv.plx
- printenv.py

printenv.pl:

#!/usr/local/bin/perl -wT

use strict;
use diagnostics;

$|++;

print "Content-Type: text/html\n\n";
print "<HTML><HEAD><TITLE>Printenv Script</TITLE></HEAD>\n";
print "<BODY>\n";
print map { "<P><B>$_</B> = $ENV{$_}</P>\n" } sort keys %ENV;
print "</BODY></HTML>\n";

$$$. dd

ddd

Results from another printenv script, as static text, actual execution - only works if server is configured accordingly (not on Internet): http://localhost:8888/cgi-bin/printenv.

400 Bad Request

500 Internal Server Error

The server encountered an unexpected condition which prevented it from fulfilling the request.

A Mac-encoded text file - uses CR for line breaks

cmdprompt> less printenv.cgi
#!/usr/local/bin/perl -wT^M^Muse strict;^Muse diagnostics;^M^M$|++;^M^Mprint "Co
ntent-Type: text/html\n\n";^Mprint "<HTML><HEAD><TITLE>Printenv Script</TITLE></
HEAD>\n";^Mprint "<BODY>\n";^Mprint map { "<P><B>$_</B> = $ENV{$_}</P>\n" } sort
 keys %ENV;^Mprint "</BODY></HTML>\n";

A UNIX (and DOS)-encoded text file - uses LF for line breaks

cmdprompt> less printenv.pl 
#!/usr/local/bin/perl -wT
use strict;
use diagnostics;
$|++;
print "Content-Type: text/html\n\n";
print "<HTML><HEAD><TITLE>Printenv Script</TITLE></HEAD>\n";
print "<BODY>\n";
print map { "<P><B>$_</B> = $ENV{$_}</P>\n" } sort keys %ENV;
print "</BODY></HTML>\n";
[johan@jp2] comgt/search>

	PHP as CGI	PHP as Module
Script file
Must have Executable flag set	Yes, get Internal error otherwise	No
	`#!/usr/bin/env php <?php print "Content-Type: text/html\n\n";?> <!DOCTYPE HTML> <html> <head> <meta charset="UTF-8"> <title>Untitled Document</title> </head> <body> <?php print "Hello, World\n"; ?> </body> </html>`	`<!DOCTYPE HTML> <html> <head> <meta charset="UTF-8"> <title>Untitled Document</title> </head> <body> <?php print "Hello, World\n"; ?> </body> </html>`
	Running the above script in Module-mode will provide browser output: #!/usr/bin/env php Content-Type: text/html Hello, World
Test material/script	php-as-cgi / show_env.php	php-as-cgi / show_env.php
php.net .. reserved.variables.php Superglobals — Superglobals are built-in variables that are always available in all scopes $GLOBALS — References all variables available in global scope $_SERVER — Server and execution environment information $_GET — HTTP GET variables $_POST — HTTP POST variables $_FILES — HTTP File Upload variables $_REQUEST — HTTP Request variables $_SESSION — Session variables $_ENV — Environment variables $_COOKIE — HTTP Cookies $php_errormsg — The previous error message $HTTP_RAW_POST_DATA — Raw POST data $http_response_header — HTTP response headers $argc — The number of arguments passed to script $argv — Array of arguments passed to script

per (2016-02-03)	1&1	IM2713

Server API	CGI/FastCGI	Apache 2.0 Handler

Updated 2016-02-03