diff options
| author | Denis Vlasenko <vda.linux@googlemail.com> | 2007-02-11 14:52:07 +0000 |
|---|---|---|
| committer | Denis Vlasenko <vda.linux@googlemail.com> | 2007-02-11 14:52:07 +0000 |
| commit | 136f42f503cb3e9588e62332d043e92b7475ec4e (patch) | |
| tree | 81c556d1a136112be07bbd2c19293e65fad03cdd /docs/cgi/env.html | |
| parent | ad67a3925c78e7c9f8e61248f640c5cc7a5cf186 (diff) | |
| download | busybox-136f42f503cb3e9588e62332d043e92b7475ec4e.tar.gz | |
Add CGI docs
Diffstat (limited to 'docs/cgi/env.html')
| -rw-r--r-- | docs/cgi/env.html | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/docs/cgi/env.html b/docs/cgi/env.html new file mode 100644 index 000000000..961671aaa --- /dev/null +++ b/docs/cgi/env.html @@ -0,0 +1,149 @@ +<html><head><title>CGI Environment Variables</title></head><body><h1><img alt="" src="env_files/CGIlogo.gif"> CGI Environment Variables</h1> +<hr> + +<p> + +In order to pass data about the information request from the server to +the script, the server uses command line arguments as well as +environment variables. These environment variables are set when the +server executes the gateway program. </p><p> + +</p><hr> +<h2>Specification</h2> + + <p> +The following environment variables are not request-specific and are +set for all requests: </p><p> + +</p><ul> +<li> <code>SERVER_SOFTWARE</code> <p> + + The name and version of the information server software answering + the request (and running the gateway). Format: name/version </p><p> + +</p></li><li> <code>SERVER_NAME</code> <p> + The server's hostname, DNS alias, or IP address as it would appear + in self-referencing URLs. </p><p> + +</p></li><li> <code>GATEWAY_INTERFACE</code> <p> + The revision of the CGI specification to which this server + complies. Format: CGI/revision</p><p> + +</p></li></ul> + +<hr> + +The following environment variables are specific to the request being +fulfilled by the gateway program: <p> + +</p><ul> +<li> <a name="protocol"><code>SERVER_PROTOCOL</code></a> <p> + The name and revision of the information protcol this request came + in with. Format: protocol/revision </p><p> + +</p></li><li> <code>SERVER_PORT</code> <p> + The port number to which the request was sent. </p><p> + +</p></li><li> <code>REQUEST_METHOD</code> <p> + The method with which the request was made. For HTTP, this is + "GET", "HEAD", "POST", etc. </p><p> + +</p></li><li> <code>PATH_INFO</code> <p> + The extra path information, as given by the client. In other + words, scripts can be accessed by their virtual pathname, followed + by extra information at the end of this path. The extra + information is sent as PATH_INFO. This information should be + decoded by the server if it comes from a URL before it is passed + to the CGI script.</p><p> + +</p></li><li> <code>PATH_TRANSLATED</code> <p> + The server provides a translated version of PATH_INFO, which takes + the path and does any virtual-to-physical mapping to it. </p><p> + +</p></li><li> <code>SCRIPT_NAME</code> <p> + A virtual path to the script being executed, used for + self-referencing URLs. </p><p> + +</p></li><li> <a name="query"><code>QUERY_STRING</code></a> <p> + The information which follows the ? in the <a href="http://www.ncsa.uiuc.edu/demoweb/url-primer.html">URL</a> + which referenced this script. This is the query information. It + should not be decoded in any fashion. This variable should always + be set when there is query information, regardless of <a href="http://hoohoo.ncsa.uiuc.edu/cgi/cl.html">command line decoding</a>. </p><p> + +</p></li><li> <code>REMOTE_HOST</code> <p> + The hostname making the request. If the server does not have this + information, it should set REMOTE_ADDR and leave this unset.</p><p> + +</p></li><li> <code>REMOTE_ADDR</code> <p> + The IP address of the remote host making the request. </p><p> + +</p></li><li> <code>AUTH_TYPE</code> <p> + If the server supports user authentication, and the script is + protects, this is the protocol-specific authentication method used + to validate the user. </p><p> + +</p></li><li> <code>REMOTE_USER</code> <p> + If the server supports user authentication, and the script is + protected, this is the username they have authenticated as. </p><p> +</p></li><li> <code>REMOTE_IDENT</code> <p> + If the HTTP server supports RFC 931 identification, then this + variable will be set to the remote user name retrieved from the + server. Usage of this variable should be limited to logging only. + </p><p> + +</p></li><li> <a name="ct"><code>CONTENT_TYPE</code></a> <p> + For queries which have attached information, such as HTTP POST and + PUT, this is the content type of the data. </p><p> + +</p></li><li> <a name="cl"><code>CONTENT_LENGTH</code></a> <p> + The length of the said content as given by the client. </p><p> + +</p></li></ul> + + +<a name="headers"><hr></a> + +In addition to these, the header lines received from the client, if +any, are placed into the environment with the prefix HTTP_ followed by +the header name. Any - characters in the header name are changed to _ +characters. The server may exclude any headers which it has already +processed, such as Authorization, Content-type, and Content-length. If +necessary, the server may choose to exclude any or all of these +headers if including them would exceed any system environment +limits. <p> + +An example of this is the HTTP_ACCEPT variable which was defined in +CGI/1.0. Another example is the header User-Agent.</p><p> + +</p><ul> +<li> <code>HTTP_ACCEPT</code> <p> + The MIME types which the client will accept, as given by HTTP + headers. Other protocols may need to get this information from + elsewhere. Each item in this list should be separated by commas as + per the HTTP spec. </p><p> + + Format: type/subtype, type/subtype </p><p> + + +</p></li><li> <code>HTTP_USER_AGENT</code><p> + + The browser the client is using to send the request. General +format: <code>software/version library/version</code>.</p><p> + +</p></li></ul> + +<hr> +<h2>Examples</h2> + +Examples of the setting of environment variables are really much better +<a href="http://hoohoo.ncsa.uiuc.edu/cgi/examples.html">demonstrated</a> than explained. <p> + +</p><hr> + +<a href="http://hoohoo.ncsa.uiuc.edu/cgi/interface.html"><img alt="[Back]" src="env_files/back.gif">Return to the +interface specification</a> <p> + +CGI - Common Gateway Interface +</p><address><a href="http://hoohoo.ncsa.uiuc.edu/cgi/mailtocgi.html">cgi@ncsa.uiuc.edu</a></address> + +</body></html>
\ No newline at end of file |