docs/mod_fastcgi.html

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   6             Apache module mod_fastcgi
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  27         <H1 CLASS="c2">
  28             Module mod_fastcgi
  29         </H1>
  30         <P>
  31             This 3<SUP>rd</SUP> party module provides support for the FastCGI protocol. FastCGI is a language
  32             independent, scalable, open extension to CGI that provides high performance and persistence without the
  33             limitations of server specific APIs.
  34         </P>
  35         <P>
  36             FastCGI applications are not limited to a particular development language (the protocol is open). FastCGI
  37             application libraries currently exist for Perl, C/C++, Java, Python, TCL, SmallEiffel, and Smalltalk.
  38         </P>
  39         <P>
  40             FastCGI applications use TCP or Unix sockets to communicate with the web server. This scalable architecture
  41             allows applications to run on the same platform as the web server or on many machines scattered across an
  42             enterprise network.
  43         </P>
  44         <P>
  45             FastCGI applications are portable to other web server platforms. FastCGI is supported either directly or
  46             through commercial extensions by most popular web servers.
  47         </P>
  48         <P>
  49             FastCGI applications are fast because they&#39;re persistent. There is no per-request startup and
  50             initialization overhead. This makes possible the development of applications which would otherwise be
  51             impractical within the CGI paradigm (e.g. a huge Perl script, or an application which requires a connection
  52             to one or more databases).
  53         </P>
  54         <P>
  55             See the FastCGI <A HREF="http://www.FastCGI.com/">website</A> for more information. To receive FastCGI
  56             related announcements and notifications of software updates, subscribe to <A HREF=
  57             "http://fastcgi.com/fastcgi-announce">fastcgi-announce</A>. To participate in the discussion of
  58             <CODE>mod_fastcgi</CODE> and FastCGI application development, subscribe to <A HREF=
  59             "http://fastcgi.com/fastcgi-developers">fastcgi-developers</A>.
  60         </P>
  61         <H2>
  62             Summary
  63         </H2>
  64         <P>
  65             For information about building and installing the module, see the <A HREF="../INSTALL">INSTALL</A> document
  66             that came with the distribution.
  67         </P>
  68         <P>
  69             FastCGI applications under <CODE>mod_fastcgi</CODE> are defined as one of three types: static, dynamic, or
  70             external. They&#39;re configured using the <A HREF="#fastcgiserver">FastCgiServer</A>, <A HREF=
  71             "#FastCgiConfig">FastCgiConfig</A>, and <A HREF="#FastCgiExternalServer">FastCgiExternalServer</A> <A HREF=
  72             "#directives">directives</A> respectively. Any URI that Apache identifies as a FastCGI application and
  73             which hasn&#39;t been explicitly configured using a <A HREF="#fastcgiserver">FastCgiServer</A> or <A HREF=
  74             "#FastCgiExternalServer">FastCgiExternalServer</A> directive is handled as a dynamic application (see the
  75             <A HREF="#FastCgiConfig">FastCgiConfig</A> directive for more information).
  76         </P>
  77         <P>
  78             FastCGI static and dynamic applications are spawned and managed by the FastCGI Process Manager, fcgi-pm.
  79             The process manager is spawned by Apache at server initialization. External applications are presumed to be
  80             started and managed independently.
  81         </P>
  82         <P>
  83             Apache must be configured to identify requests for FastCGI URIs. <CODE>mod_fastcgi</CODE> registers (with
  84             Apache) a handler type of <CODE>fastcgi-script</CODE> for this purpose.
  85         </P>
  86         <P>
  87             To configure Apache to handle all files (within the scope of the directive) as FastCGI applications (e.g.
  88             for a fcgi-bin directory):
  89         </P>
  90         <BLOCKQUOTE>
  91             <P>
  92                 <CODE><A HREF="http://httpd.apache.org/docs/mod/mod_mime.html#sethandler">SetHandler</A>
  93                 fastcgi-script</CODE>
  94             </P>
  95         </BLOCKQUOTE>
  96         <P>
  97             To configure Apache to handle files (within the scope of the directive) with the specified extension(s) as
  98             FastCGI applications:
  99         </P>
 100         <BLOCKQUOTE>
 101             <P>
 102                 <CODE><A HREF="http://httpd.apache.org/docs/mod/mod_mime.html#addhandler">AddHandler</A> fastcgi-script
 103                 fcg fcgi fpl</CODE>
 104             </P>
 105         </BLOCKQUOTE>
 106         <P>
 107             Consult the Apache documentation for more information regarding these and other directives which affect
 108             request handling (such as <CODE><A HREF=
 109             "http://httpd.apache.org/docs/mod/mod_actions.html#action">Action</A>).</CODE>
 110         </P>
 111         <P>
 112             Dynamic FastCGI applications require the <CODE>ExecCGI</CODE> option be enabled (see the <A HREF=
 113             "http://httpd.apache.org/docs/mod/core.html#options"><CODE>Options</CODE></A> directive) in the
 114             application&#39;s directory.
 115         </P>
 116         <H2>
 117             Notes
 118         </H2>
 119         <P>
 120             <CODE>mod_fastcgi</CODE> logs FastCGI application error (stderr) output to the server log associated with
 121             the request. Errors reported by the FastCGI process manager, fcgi-pm, are reported to the main server log
 122             (typically, logs/error_log). Data written to stdout or stderr before entering the FastCGI <EM>accept</EM>
 123             loop or via a mechanism that is not FastCGI protocol aware will also be directed to the main server log. If
 124             Apache&#39;s <A HREF="http://httpd.apache.org/docs/mod/core.html#loglevel"><CODE>LogLevel</CODE></A> is set
 125             to <CODE>info</CODE> additional informational messages are printed to the logs, these messages may be
 126             especially helpful while debugging a configuration.
 127         </P>
 128         <P>
 129             Under Unix, expect your FastCGI application to see SIGPIPE, SIGUSR1, and SIGTERM. The latest FastCGI C, C++
 130             and Perl application library installs default handlers if none are installed by the application. If an http
 131             client aborts a request before it completes, mod_fastcgi does too - this results in a SIGPIPE to the
 132             FastCGI application. At a minimum, SIGPIPE should be ignored (applications spawned by mod_fastcgi have this
 133             setup automatically). Ideally, it should result in an early abort of the request handling within your
 134             application and a return to the top of the FastCGI accept() loop. Apache uses SIGUSR1 to request a
 135             &quot;graceful&quot; process restart/shutdown. It is sent to Apache&#39;s process group (which includes
 136             applications spawned by mod_fastcgi). Ideally, it should result in a FastCGI application finishing the
 137             current request, if any, and then an exit. The mod_fastcgi process manager isn&#39;t particularly patient
 138             though (there&#39;s room for improvement here) and since it has to shutdown too, sends a SIGTERM to all of
 139             the FastCGI applications it is responsible for. Apache will restart the process manager and it will restart
 140             its managed applications (as if the server was just started). SIGTERM is, well, SIGTERM - your application
 141             should exit quickly.
 142         </P>
 143         <P>
 144             Under Windows, there are no signals. A shutdown event is used instead. This is setup by mod_fastcgi and
 145             honored by the latest version of the C, C++, and Perl application library. If your using a library which
 146             doesn&#39;t support this, your application will not get shutdown during an Apache restart/shutdown
 147             (there&#39;s room for improvement here).
 148         </P>
 149         <P>
 150             To pass per-request environment variables to FastCGI applications, have a look at: <A HREF=
 151             "http://httpd.apache.org/docs/mod/mod_env.html"><CODE>mod_env</CODE></A> (<CODE>SetEnv</CODE>,
 152             <CODE>PassEnv</CODE>, <CODE>UnSetEnv</CODE>), <A HREF=
 153             "http://httpd.apache.org/docs/mod/mod_setenvif.html"><CODE>mod_setenvif</CODE></A>
 154             (<CODE>BrowserMatch</CODE>, <CODE>BrowserMatchNoCase</CODE>, <CODE>SetEnvIf</CODE>,
 155             <CODE>SetEnvIfNoCase</CODE>), and <A HREF=
 156             "http://httpd.apache.org/docs/mod/mod_rewrite.html"><CODE>mod_rewrite</CODE></A> (if you&#39;re feeling
 157             adventurous).
 158         </P>
 159         <P>
 160             FastCGI application output is buffered by default. This is not the case for CGI scripts (under Apache 1.3).
 161             To override the default behavior, use the <CODE>-flush</CODE> option (not available for dynamic
 162             applications). Non-parsed header (nph-) scripts will be rejected by mod_fastcgi simply as warning the
 163             behavior is different (create a symbolic link to the script without the &quot;nph-&quot; prefix if this
 164             poses a problem).
 165         </P>
 166         <P>
 167             Redirects are handled similarly to CGI. Location headers with values that begin with &quot;/&quot; are
 168             treated as internal-redirects; otherwise, they are treated as external redirects (302).
 169         </P>
 170         <P>
 171             Session affinity (as well as distribution) should be achievable outside of <CODE>mod_fastcgi</CODE> using
 172             <A HREF="http://httpd.apache.org/docs/mod/mod_rewrite.html"><CODE>mod_rewrite</CODE></A>. If you get this
 173             working, please post the details to <A HREF=
 174             "mailto:fastcgi-developers@fastcgi.com">fastcgi-developers@fastcgi.com</A> so they can be included here.
 175         </P>
 176         <H2>
 177             FastCGI Specification Compliance
 178         </H2>
 179         <P>
 180             The FastCGI specification is not implemented in its entirety and I&#39;ve deviated a bit as well resulting
 181             in some Apache specific features.
 182         </P>
 183         <P>
 184             The file descriptors for stdout and stderr are left open. This is prohibited by the specification. I
 185             can&#39;t see any reason to require that they be closed, and leaving them open prevents FastCGI
 186             applications which were not completely ported to FastCGI from failing miserably. This does not mean the
 187             applications shouldn&#39;t be fixed such that this doesn&#39;t occur, but is invaluable when using a
 188             3<SUP>rd</SUP> party library (without source code) which expects to be able to write to stderr. Anything
 189             written to stdout or stderr in this manner will be directed to the main server log.
 190         </P>
 191         <P>
 192             The Filter and Log Roles are not supported. The Filter Role has little value in Apache until the output of
 193             one handler can be piped into another (Apache 2.0 is expected to support this). The Log Role has some
 194             value, but Apache&#39;s &quot;piped logs&quot; feature is similar (and is even more CPU friendly).
 195         </P>
 196         <P>
 197             The FastCGI protocol supports a feature, described in the specificiation as &quot;multiplexing&quot;, that
 198             allows a single client-server connection to be simultaneously shared by multiple requests. This is not
 199             supported. This does *not* prevent FastCGI applications from supporting multiple simultaneous requests over
 200             independent connections. Of course, the application has to be specifically designed to do so by using a
 201             threaded or select/poll based server model.
 202         </P>
 203         <P>
 204             The Authorizer Role has three variations corresponding to three specific Apache request handling
 205             phases:&nbsp; Authentication, Authorization, and Access Control. <CODE>mod_fastcgi</CODE> sets up the
 206             (Apache specific) environment variable &quot;FCGI_APACHE_ROLE&quot; to indicate which Apache authorizer
 207             phase is being performed.
 208         </P>
 209         <P>
 210             Authorizers under <CODE>mod_fastcgi</CODE> are sent nearly all of the standard environment variables
 211             typically available to CGI/FastCGI request handlers including some explicitly precluded by the FastCGI
 212             specification (for authorizers); I didn&#39;t see the point in leaving them out. All headers returned by a
 213             FastCGI Authorizer in a successful response (Status: 200) are passed to sub-processes (CGI/FastCGI
 214             invocations) as environment variables rather than just those prefixed by <CODE>Variable-</CODE> as the
 215             FastCGI specification calls for; I didn&#39;t see the point in leaving them out either. FastCGI
 216             specification compliant authorizer behavior can be obtained by using the <CODE>-compat</CODE> option to the
 217             Auth server directives.
 218         </P>
 219         <P>
 220             Custom failure responses from FastCGI authorizer applications are not supported (speak up if you need
 221             this). See the <A HREF="http://httpd.apache.org/docs/mod/core.html#errordocument">ErrorDocument</A>
 222             directive for a workaround (a CGI/FastCGI application can serve the error document).
 223         </P>
 224         <H2>
 225             <A NAME="directives">Directives</A>
 226         </H2>
 227         <UL>
 228             <LI>
 229                 <A HREF="#FastCgiServer"><CODE>FastCgiServer</CODE></A>
 230             </LI>
 231             <LI>
 232                 <A HREF="#FastCgiConfig"><CODE>FastCgiConfig</CODE></A>
 233             </LI>
 234             <LI>
 235                 <A HREF="#FastCgiExternalServer"><CODE>FastCgiExternalServer</CODE></A>
 236             </LI>
 237             <LI>
 238                 <A HREF="#FastCgiIpcDir"><CODE>FastCgiIpcDir</CODE></A>
 239             </LI>
 240             <LI>
 241                 <A HREF="#FastCgiWrapper"><CODE>FastCgiWrapper</CODE></A>
 242             </LI>
 243             <LI>
 244                 <A HREF="#FastCgiAuthenticator"><CODE>FastCgiAuthenticator</CODE></A>
 245             </LI>
 246             <LI>
 247                 <A HREF="#FastCgiAuthenticatorAuthoritative"><CODE>FastCgiAuthenticatorAuthoritative</CODE></A>
 248             </LI>
 249             <LI>
 250                 <A HREF="#FastCgiAuthorizer"><CODE>FastCgiAuthorizer</CODE></A>
 251             </LI>
 252             <LI>
 253                 <A HREF="#FastCgiAuthorizerAuthoritative"><CODE>FastCgiAuthorizerAuthoritative</CODE></A>
 254             </LI>
 255             <LI>
 256                 <A HREF="#FastCgiAccessChecker"><CODE>FastCgiAccessChecker</CODE></A>
 257             </LI>
 258             <LI>
 259                 <A HREF="#FastCgiAccessCheckerAuthoritative"><CODE>FastCgiAccessCheckerAuthoritative</CODE></A>
 260             </LI>
 261         </UL>
 262         <HR>
 263         <H2>
 264             <A NAME="FastCgiServer">FastCgiServer</A>
 265         </H2>
 266         <!-- %plaintext &lt;?INDEX {\tt FastCgiServer} directive&gt; -->
 267         <TABLE BORDER="0" SUMMARY="">
 268             <TR>
 269                 <TD>
 270                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
 271                     "Help"><STRONG>Syntax:</STRONG></A>
 272                 </TD>
 273                 <TD>
 274                     <CODE>FastCgiServer <EM>filename</EM> <EM>[option ...]</EM></CODE>
 275                 </TD>
 276             </TR>
 277             <TR>
 278                 <TD>
 279                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
 280                     "Help"><STRONG>Context:</STRONG></A>
 281                 </TD>
 282                 <TD>
 283                     server config
 284                 </TD>
 285             </TR>
 286         </TABLE>
 287         <P>
 288             The <CODE>FastCgiServer</CODE> directive defines <EM>filename</EM> as a static FastCGI application. If the
 289             filename does not begin with a slash (/) then it is assumed to be relative to the <A HREF=
 290             "http://httpd.apache.org/docs/mod/core.html#serverroot">ServerRoot</A>.
 291         </P>
 292         <P>
 293             By default, the Process Manager will start one instance of the application with the default configuration
 294             specified (in parentheses) below. Should a static application instance die for any reason
 295             <CODE>mod_fastcgi</CODE> will spawn another to replace it and log the event (at the <CODE>warn</CODE> <A
 296             HREF="http://httpd.apache.org/docs/mod/core.html#loglevel"><CODE>LogLevel</CODE></A>).
 297         </P>
 298         <P>
 299             <EM>Option</EM> can be one of (case insensitive):
 300         </P>
 301         <DL>
 302             <DT>
 303                 <CODE><STRONG>-appConnTimeout <EM>n</EM></STRONG> (0 seconds)</CODE>
 304             </DT>
 305             <DD>
 306                 <STRONG>Unix:&nbsp;</STRONG> The number of seconds to wait for a connection to the FastCGI application
 307                 to complete or 0 to indicate a blocking <CODE>connect()</CODE> should be used. Blocking
 308                 <CODE>connect()</CODE>s have an OS dependent internal timeout<CODE>.</CODE> If the timeout expires, a
 309                 SERVER_ERROR results. For non-zero values, this is the amount of time used in a <CODE>select()</CODE>
 310                 to write to the file descriptor returned by a non-blocking <CODE>connect().</CODE> Non-blocking
 311                 <CODE>connect()</CODE>s are troublesome on many platforms. See also <CODE>-idle-timeout</CODE>, it
 312                 produces similar results but in a more portable manner.<BR>
 313                  <STRONG>Windows NT:&nbsp;</STRONG> TCP based applications work as above. Named pipe based applications
 314                 (static applications configured without the <CODE>-port</CODE> option and dynamic applications) use
 315                 this value successfully to limit the amount of time to wait for a connection (i.e. it&#39;s not
 316                 &quot;troublesome&quot;). By default, this is 90 seconds (FCGI_NAMED_PIPE_CONNECT_TIMEOUT in
 317                 mod_fastcgi.h).
 318             </DD>
 319             <DT>
 320                 <CODE><STRONG>-idle-timeout <EM>n</EM></STRONG> (30 seconds)</CODE>
 321             </DT>
 322             <DD>
 323                 The number of seconds of FastCGI application inactivity allowed before the request is aborted and the
 324                 event is logged (at the <CODE>error</CODE> <A HREF=
 325                 "http://httpd.apache.org/docs/mod/core.html#loglevel"><CODE>LogLevel</CODE></A>). The inactivity timer
 326                 applies only as long as a connection is pending with the FastCGI application. If a request is queued to
 327                 an application, but the application doesn&#39;t respond (by writing and flushing) within this period,
 328                 the request will be aborted. If communication is complete with the application but incomplete with the
 329                 client (the response is buffered), the timeout does not apply.
 330             </DD>
 331             <DT>
 332                 <CODE><STRONG>-initial-env <EM>name[=[value]]</EM></STRONG> (none)</CODE>
 333             </DT>
 334             <DD>
 335                 A name-value pair to be passed in the FastCGI application&#39;s <EM>initial</EM> environment. To pass a
 336                 variable from Apache&#39;s environment, don&#39;t provide the &quot;=&quot; (if the variable isn&#39;t
 337                 actually in the environment, it will be defined without a value). To define a variable without a value,
 338                 provide the &quot;=&quot; without any value. The option can be used repeatedly.
 339             </DD>
 340             <DT>
 341                 <CODE><STRONG>-init-start-delay <EM>n</EM></STRONG> (1 second)</CODE>
 342             </DT>
 343             <DD>
 344                 The minimum number of seconds between the spawning of instances of this application. This delay
 345                 decreases the demand placed on the system at server initialization.
 346             </DD>
 347             <DT>
 348                 <CODE><STRONG>-flush</STRONG> (none)</CODE>
 349             </DT>
 350             <DD>
 351                 Force a write to the client as data is received from the application. By default,
 352                 <CODE>mod_fastcgi</CODE> buffers data in order to free the application as quickly as possible.
 353             </DD>
 354             <DT>
 355                 <CODE><STRONG>-listen-queue-depth <EM>n</EM></STRONG> (100)</CODE>
 356             </DT>
 357             <DD>
 358                 The depth of <CODE>listen()</CODE> queue (also known as the backlog) shared by all of the instances of
 359                 this application. A deeper listen queue allows the server to cope with transient load fluctuations
 360                 without rejecting requests; it does not increase throughput. Adding additional application instances
 361                 may increase throughput/performance, depending upon the application and the host.
 362             </DD>
 363             <DT>
 364                 <CODE><STRONG>-pass-header <EM>header</EM></STRONG> (none)</CODE>
 365             </DT>
 366             <DD>
 367                 The name of an HTTP Request Header to be passed in the <EM>request</EM> environment. This option makes
 368                 available the contents of headers which are normally not available (e.g. Authorization) to a CGI
 369                 environment.
 370             </DD>
 371             <DT>
 372                 <CODE><STRONG>-port <EM>n</EM></STRONG> (none)</CODE>
 373             </DT>
 374             <DD>
 375                 The TCP port number (1-65535) the application will use for communication with the web server. This
 376                 option makes the application accessible from other machines on the network (as well as this one). The
 377                 <CODE>-socket</CODE> and <CODE>-port</CODE> options are mutually exclusive.
 378             </DD>
 379             <DT>
 380                 <CODE><STRONG>-priority <EM>n</EM></STRONG> (0)</CODE>
 381             </DT>
 382             <DD>
 383                 The process priority to be assigned to the application instances (using <CODE>setpriority()</CODE>).
 384             </DD>
 385             <DT>
 386                 <CODE><STRONG>-processes <EM>n</EM></STRONG> (1)</CODE>
 387             </DT>
 388             <DD>
 389                 The number of instances of the application to spawn at server initialization.
 390             </DD>
 391             <DT>
 392                 <CODE><STRONG>-restart-delay <EM>n</EM></STRONG> (5 seconds)</CODE>
 393             </DT>
 394             <DD>
 395                 The minimum number of seconds between the respawning of failed instances of this application. This
 396                 delay prevents a broken application from soaking up too much of the system.
 397             </DD>
 398             <DT>
 399                 <CODE><STRONG>-socket <EM>filename</EM></STRONG> (generated)</CODE>
 400             </DT>
 401             <DD>
 402                 <STRONG>Unix:&nbsp;</STRONG> The filename of the Unix domain socket that the application will use for
 403                 communication with the web server. The module creates the socket within the directory specified by
 404                 <CODE><A HREF="#FastCgiIpcDir">FastCgiIpcDir</A></CODE>. This option makes the application accessible
 405                 to other applications (e.g. <CODE>cgi-fcgi</CODE>) on the same machine or via an external FastCGI
 406                 application definition (<CODE><A HREF="#FastCgiExternalServer">FastCgiExternalServer</A></CODE>). If
 407                 neither the <CODE>-socket</CODE> nor the <CODE>-port</CODE> options are given, the module generates a
 408                 Unix domain socket filename. The <CODE>-socket</CODE> and <CODE>-port</CODE> options are mutually
 409                 exclusive.
 410             </DD>
 411             <DD>
 412                 <STRONG>Windows NT:&nbsp;</STRONG> The name of the named pipe that the application will use for
 413                 communication with the web server. The module creates the named pipe under the named pipe root
 414                 specified by <CODE><A HREF="#FastCgiIpcDir">FastCgiIpcDir</A></CODE>. This option makes the application
 415                 accessible to other applications (e.g. <CODE>cgi-fcgi</CODE>) on the same machine or via an external
 416                 FastCGI application definition (<CODE><A HREF=
 417                 "#FastCgiExternalServer">FastCgiExternalServer</A></CODE>). If neither the <CODE>-socket</CODE> nor the
 418                 <CODE>-port</CODE> options are given, the module generates a name for the named pipe. The
 419                 <CODE>-socket</CODE> and <CODE>-port</CODE> options are mutually exclusive.
 420             </DD>
 421         </DL>
 422         <HR>
 423         <H2>
 424             <A NAME="FastCgiConfig">FastCgiConfig</A>
 425         </H2>
 426         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
 427         <TABLE BORDER="0" SUMMARY="">
 428             <TR>
 429                 <TD>
 430                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
 431                     "Help"><STRONG>Syntax:</STRONG></A>
 432                 </TD>
 433                 <TD>
 434                     <CODE>FastCgiConfig <EM>option [option ...]</EM></CODE>
 435                 </TD>
 436             </TR>
 437             <TR>
 438                 <TD>
 439                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
 440                     "Help"><STRONG>Context:</STRONG></A>
 441                 </TD>
 442                 <TD>
 443                     server config
 444                 </TD>
 445             </TR>
 446         </TABLE>
 447         <P>
 448             The <CODE>FastCgiConfig</CODE> directive defines the default parameters for <EM>all</EM> dynamic FastCGI
 449             applications. This directive does not affect static or external applications in any way.
 450         </P>
 451         <P>
 452             Dynamic applications are not started at server initialization, but upon demand. If the demand is heavy,
 453             additional application instances are started. As the demand fades, application instances are killed off.
 454             Many of the options govern this process.
 455         </P>
 456         <P>
 457             <EM>Option</EM> can be one of (case insensitive):
 458         </P>
 459         <DL>
 460             <DT>
 461                 <CODE><STRONG>-appConnTimeout <EM>n</EM></STRONG> (0 seconds)</CODE>
 462             </DT>
 463             <DD>
 464                 <STRONG>Unix:&nbsp;</STRONG> The number of seconds to wait for a connection to the FastCGI application
 465                 to complete or 0 to indicate a blocking <CODE>connect()</CODE> should be used. Blocking
 466                 <CODE>connect()</CODE>s have an OS dependent internal timeout. If the timeout expires, a SERVER_ERROR
 467                 results. For non-zero values, this is the amount of time used in a <CODE>select()</CODE> to write to
 468                 the file descriptor returned by a non-blocking <CODE>connect()</CODE>. Non-blocking
 469                 <CODE>connect()</CODE>s are troublesome on many platforms. See also <CODE>-idle-timeout</CODE>, it
 470                 produces similar results but in a more portable manner.<BR>
 471                  <STRONG>Windows NT:&nbsp;</STRONG> TCP based applications work as above. Named pipe based applications
 472                 (static applications configured without the <CODE>-port</CODE> option and dynamic applications) use
 473                 this value successfully to limit the amount of time to wait for a connection (i.e. it&#39;s not
 474                 &quot;troublesome&quot;). By default, this is 90 seconds (FCGI_NAMED_PIPE_CONNECT_TIMEOUT in
 475                 mod_fastcgi.h).
 476             </DD>
 477             <DT>
 478                 <CODE><STRONG>-autoUpdate</STRONG> (none)</CODE>
 479             </DT>
 480             <DD>
 481                 Causes mod_fastcgi to check the modification time of the application on disk before processing each
 482                 request. If the application on disk has been changed, the process manager is notified and all running
 483                 instances of the application are killed off. In general, it&#39;s preferred that this type of
 484                 functionality be built-in to the application (e.g. every 100th request it checks to see if there&#39;s
 485                 a newer version on disk and exits if so). There may be an outstanding problem (bug) when this option is
 486                 used with <CODE>-restart</CODE>.
 487             </DD>
 488             <DT>
 489                 <CODE><STRONG>-flush</STRONG> (none)</CODE>
 490             </DT>
 491             <DD>
 492                 Force a write to the client as data is received from the application. By default,
 493                 <CODE>mod_fastcgi</CODE> buffers data in order to free the application as quickly as possible.
 494             </DD>
 495             <DT>
 496                 <CODE><STRONG>-gainValue <EM>n</EM></STRONG> (0.5)</CODE>
 497             </DT>
 498             <DD>
 499                 A floating point value between 0 and 1 used as an exponent in the computation of the exponentially
 500                 decayed connection times load factor of the currently running dynamic FastCGI applications. Old values
 501                 are scaled by (<CODE>1&nbsp;-&nbsp;gainValue</CODE>), so making it smaller weights old values more than
 502                 the current value (which is scaled by <CODE>gainValue</CODE>).
 503             </DD>
 504             <DT>
 505                 <CODE><STRONG>-idle-timeout <EM>n</EM></STRONG> (30 seconds)</CODE>
 506             </DT>
 507             <DD>
 508                 The number of seconds of FastCGI application inactivity allowed before the request is aborted and the
 509                 event is logged (at the <CODE>error</CODE> <A HREF=
 510                 "http://httpd.apache.org/docs/mod/core.html#loglevel"><CODE>LogLevel</CODE></A>). The inactivity timer
 511                 applies only as long as a connection is pending with the FastCGI application. If a request is queued to
 512                 an application, but the application doesn&#39;t respond (by writing and flushing) within this period,
 513                 the request will be aborted. If communication is complete with the application but incomplete with the
 514                 client (the response is buffered), the timeout does not apply.
 515             </DD>
 516             <DT>
 517                 <CODE><STRONG>-initial-env <EM>name[=[value]]</EM></STRONG> (none)</CODE>
 518             </DT>
 519             <DD>
 520                 A name-value pair to be passed in the initial environment when instances of applications are spawned.
 521                 To pass a variable from the Apache environment, don&#39;t provide the &quot;=&quot; (if the variable
 522                 isn&#39;t actually in the environment, it will be defined without a value). To define a variable
 523                 without a value, provide the &quot;=&quot; without any value. The option can be used repeatedly.
 524             </DD>
 525             <DT>
 526                 <CODE><STRONG>-init-start-delay <EM>n</EM></STRONG> (1 second)</CODE>
 527             </DT>
 528             <DD>
 529                 The minimum number of seconds between the spawning of instances of applications. This delay decreases
 530                 the demand placed on the system at server initialization.
 531             </DD>
 532             <DT>
 533                 <CODE><STRONG>-killInterval <EM>n</EM></STRONG> (300 seconds)</CODE>
 534             </DT>
 535             <DD>
 536                 Determines how often the dynamic application instance killing policy is implemented within the process
 537                 manager. Smaller numbers result in a more aggressive policy, larger numbers a less aggressive policy.
 538             </DD>
 539             <DT>
 540                 <CODE><STRONG>-listen-queue-depth <EM>n</EM></STRONG> (100)</CODE>
 541             </DT>
 542             <DD>
 543                 The depth of <CODE>listen()</CODE> queue (also known as the backlog) shared by all instances of
 544                 applications. A deeper listen queue allows the server to cope with transient load fluctuations without
 545                 rejecting requests; it does not increase throughput. Adding additional application instances may
 546                 increase throughput/performance, depending upon the application and the host.
 547             </DD>
 548             <DT>
 549                 <CODE><STRONG>-maxClassProcesses <EM>n</EM></STRONG> (10)</CODE>
 550             </DT>
 551             <DD>
 552                 The maximum number of dynamic FastCGI application instances allowed to run for any one FastCGI
 553                 application. It must be &lt;= to -maxProcesses (this is not programmatically enforced).
 554             </DD>
 555             <DT>
 556                 <CODE><STRONG>-maxProcesses <EM>n</EM></STRONG> (50)</CODE>
 557             </DT>
 558             <DD>
 559                 The maximum total number of dynamic FastCGI application instances allowed to run at any one time. It
 560                 must be &gt;= to -maxClassProcesses (this is not programmatically enforced).
 561             </DD>
 562             <DT>
 563                 <CODE><STRONG>-minProcesses <EM>n</EM></STRONG> (5)</CODE>
 564             </DT>
 565             <DD>
 566                 The minimum total number of dynamic FastCGI application instances allowed to run at any one time
 567                 without being killed off by the process manager (due to lack of demand).
 568             </DD>
 569             <DT>
 570                 <CODE><STRONG>-multiThreshold <EM>n</EM></STRONG> (50)</CODE>
 571             </DT>
 572             <DD>
 573                 An integer between 0 and 100 used to determine whether any one instance of a FastCGI application should
 574                 be terminated. If the application has more than one instance currently running, this attribute will be
 575                 used to decide whether one of them should be terminated. If only one instance remains,
 576                 <CODE>singleThreshold</CODE> is used instead.<BR>
 577                  For historic reasons the mis-spelling <CODE>multiThreshhold</CODE> is also accepted.
 578             </DD>
 579             <DT>
 580                 <CODE><STRONG>-pass-header <EM>header</EM></STRONG> (none)</CODE>
 581             </DT>
 582             <DD>
 583                 The name of an HTTP Request Header to be passed in the <EM>request</EM> environment. This option makes
 584                 available the contents of headers which are normally not available (e.g. Authorization) to a CGI
 585                 environment.
 586             </DD>
 587             <DT>
 588                 <CODE><STRONG>-priority <EM>n</EM></STRONG> (0)</CODE>
 589             </DT>
 590             <DD>
 591                 The process priority to be assigned to the application instances (using <CODE>setpriority()</CODE>).
 592             </DD>
 593             <DT>
 594                 <CODE><STRONG>-processSlack <EM>n</EM></STRONG> (5)</CODE>
 595             </DT>
 596             <DD>
 597                 If the sum of the number of all currently running dynamic FastCGI applications and
 598                 <CODE>processSlack</CODE> exceeds <CODE>maxProcesses</CODE>, the process manager invokes the killing
 599                 policy. This is to improve performance at higher loads by killing some of the most inactive application
 600                 instances before reaching <CODE>maxProcesses</CODE>.
 601             </DD>
 602             <DT>
 603                 <CODE><STRONG>-restart</STRONG> (none)</CODE>
 604             </DT>
 605             <DD>
 606                 Causes the process manager to restart dynamic applications upon failure (similar to static
 607                 applications).
 608             </DD>
 609             <DT>
 610                 <CODE><STRONG>-restart-delay <EM>n</EM></STRONG> (5 seconds)</CODE>
 611             </DT>
 612             <DD>
 613                 The minimum number of seconds between the respawning of failed instances of applications. This delay
 614                 prevents a broken application from soaking up too much of the system.
 615             </DD>
 616             <DT>
 617                 <CODE><STRONG>-singleThreshold <EM>n</EM></STRONG> (0)</CODE>
 618             </DT>
 619             <DD>
 620                 An integer between 0 and 100 used to determine whether the last instance of a FastCGI application can
 621                 be terminated. If the process manager computed load factor for the application is lower than the
 622                 specified threshold, the last instance is terminated. In order to make your executables run in the
 623                 &quot;idle&quot; mode for the long time, you would specify a value closer to 1, however if memory or
 624                 CPU time is of primary concern, a value closer to 100 would be more applicable. A value of 0 will
 625                 prevent the last instance of an application from being terminated; this is the default value, changing
 626                 it is not recommended (especially if <CODE>-appConnTimeout</CODE> is set).<BR>
 627                  For historic reasons the mis-spelling <CODE>singleThreshhold</CODE> is also accepted.
 628             </DD>
 629             <DT>
 630                 <CODE><STRONG>-startDelay <EM>n</EM></STRONG> (3 seconds)</CODE>
 631             </DT>
 632             <DD>
 633                 The number of seconds the web server waits patiently while trying to connect to a dynamic FastCGI
 634                 application. If the interval expires, the process manager is notified with hope it will start another
 635                 instance of the application. The <CODE>startDelay</CODE> must be less than <CODE>appConnTimeout</CODE>
 636                 to be effective.
 637             </DD>
 638             <DT>
 639                 <CODE><STRONG>-updateInterval <EM>n</EM></STRONG> (300 seconds)</CODE>
 640             </DT>
 641             <DD>
 642                 The updateInterval determines how often statistical analysis is performed to determine the fate of
 643                 dynamic FastCGI applications.
 644             </DD>
 645         </DL>
 646         <HR>
 647         <H2>
 648             <A NAME="FastCgiExternalServer">FastCgiExternalServer</A>
 649         </H2>
 650         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
 651         <TABLE BORDER="0" SUMMARY="">
 652             <TR>
 653                 <TD>
 654                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
 655                     "Help"><STRONG>Syntax:</STRONG></A>
 656                 </TD>
 657                 <TD>
 658                     <CODE>FastCgiExternalServer <EM>filename</EM> -host <EM>hostname:port [option ...]</EM></CODE>
 659                 </TD>
 660             </TR>
 661             <TR>
 662                 <TD>
 663                 </TD>
 664                 <TD>
 665                     <CODE>FastCgiExternalServer <EM>filename</EM> -socket <EM>filename [option ...]</EM></CODE>
 666                 </TD>
 667             </TR>
 668             <TR>
 669                 <TD>
 670                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
 671                     "Help"><STRONG>Context:</STRONG></A>
 672                 </TD>
 673                 <TD>
 674                     server config
 675                 </TD>
 676             </TR>
 677         </TABLE>
 678         <P>
 679             The <CODE>FastCgiExternalServer</CODE> directive defines <EM>filename</EM> as an external FastCGI
 680             application. If <EM>filename</EM> does not begin with a slash (/) then it is assumed to be relative to the
 681             <A HREF="http://httpd.apache.org/docs/mod/core.html#serverroot">ServerRoot</A>. The <EM>filename</EM> does
 682             not have to exist in the local filesystem. URIs that Apache resolves to this <EM>filename</EM> will be
 683             handled by this external FastCGI application..
 684         </P>
 685         <P>
 686             External FastCGI applications are not started by the process manager, they are presumed to be started and
 687             managed &quot;external&quot; to Apache and mod_fastcgi. The FastCGI devkit provides a simple tool,
 688             <CODE>cgi-fcgi</CODE>, for starting FastCGI applications independent of the server (applications can also
 689             be <EM>self-starting</EM>, see the devkit).
 690         </P>
 691         <P>
 692             <EM>Option</EM> can be one of (case insensitive):
 693         </P>
 694         <DL>
 695             <DT>
 696                 <CODE><STRONG>-appConnTimeout <EM>n</EM></STRONG> (0 seconds)</CODE>
 697             </DT>
 698             <DD>
 699                 <STRONG>Unix:&nbsp;</STRONG> The number of seconds to wait for a connection to the FastCGI application
 700                 to complete or 0 to indicate a blocking <CODE>connect()</CODE> should be used. Blocking
 701                 <CODE>connect()</CODE>s have an OS dependent internal timeout. If the timeout expires, a SERVER_ERROR
 702                 results. For non-zero values, this is the amount of time used in a <CODE>select()</CODE> to write to
 703                 the file descriptor returned by a non-blocking <CODE>connect()</CODE>. Non-blocking
 704                 <CODE>connect()</CODE>s are troublesome on many platforms. See also <CODE>-idle-timeout</CODE>, it
 705                 produces similar results but in a more portable manner.<BR>
 706                  <STRONG>Windows NT:&nbsp;</STRONG> TCP based applications work as above. Named pipe based applications
 707                 (static applications configured without the <CODE>-port</CODE> option and dynamic applications) use
 708                 this value successfully to limit the amount of time to wait for a connection (i.e. it&#39;s not
 709                 &quot;troublesome&quot;). By default, this is 90 seconds (FCGI_NAMED_PIPE_CONNECT_TIMEOUT in
 710                 mod_fastcgi.h).
 711             </DD>
 712             <DT>
 713                 <CODE><STRONG>-idle-timeout <EM>n</EM></STRONG> (30 seconds)</CODE>
 714             </DT>
 715             <DD>
 716                 The number of seconds of FastCGI application inactivity allowed before the request is aborted and the
 717                 event is logged (at the <CODE>error</CODE> <A HREF=
 718                 "http://httpd.apache.org/docs/mod/core.html#loglevel"><CODE>LogLevel</CODE></A>). The inactivity timer
 719                 applies only as long as a connection is pending with the FastCGI application. If a request is queued to
 720                 an application, but the application doesn&#39;t respond (by writing and flushing) within this period,
 721                 the request will be aborted. If communication is complete with the application but incomplete with the
 722                 client (the response is buffered), the timeout does not apply.
 723             </DD>
 724             <DT>
 725                 <CODE><STRONG>-flush</STRONG> (none)</CODE>
 726             </DT>
 727             <DD>
 728                 Force a write to the client as data is received from the application. By default,
 729                 <CODE>mod_fastcgi</CODE> buffers data in order to free the application as quickly as possible.
 730             </DD>
 731             <DT>
 732                 <CODE><STRONG>-host <EM>hostname:port</EM></STRONG> (none)</CODE>
 733             </DT>
 734             <DD>
 735                 The hostname or IP address and TCP port number (1-65535) the application uses for communication with
 736                 the web server. The <CODE>-socket</CODE> and <CODE>-host</CODE> options are mutually exclusive.
 737             </DD>
 738             <DT>
 739                 <CODE><STRONG>-pass-header <EM>header</EM></STRONG> (none)</CODE>
 740             </DT>
 741             <DD>
 742                 The name of an HTTP Request Header to be passed in the <EM>request</EM> environment. This option makes
 743                 available the contents of headers which are normally not available (e.g. Authorization) to a CGI
 744                 environment.
 745             </DD>
 746             <DT>
 747                 <CODE><STRONG>-socket <EM>filename</EM></STRONG> (none)</CODE>
 748             </DT>
 749             <DD>
 750                 <STRONG>Unix:&nbsp;</STRONG> The filename of the Unix domain socket the application uses for
 751                 communication with the web server. The filename is relative to the <CODE><A HREF=
 752                 "#FastCgiIpcDir">FastCgiIpcDir</A></CODE>. The <CODE>-socket</CODE> and <CODE>-port</CODE> options are
 753                 mutually exclusive.
 754             </DD>
 755             <DD>
 756                 <STRONG>Windows NT:&nbsp;</STRONG> The name of the named pipe the application uses for communicating
 757                 with the web server. the name is relative to the <CODE><A HREF=
 758                 "#FastCgiIpcDir">FastCgiIpcDir</A></CODE>. The <CODE>-socket</CODE> and <CODE>-port</CODE> options are
 759                 mutually exclusive.
 760             </DD>
 761         </DL>
 762         <HR>
 763         <H2>
 764             <A NAME="FastCgiIpcDir">FastCgiIpcDir</A>
 765         </H2>
 766         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
 767         <TABLE BORDER="0" SUMMARY="">
 768             <TR>
 769                 <TD>
 770                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
 771                     "Help"><STRONG>Syntax:</STRONG></A>
 772                 </TD>
 773                 <TD>
 774                     <STRONG>Unix:&nbsp;</STRONG> <CODE>FastCgiIpcDir <EM>directory</EM></CODE>
 775                 </TD>
 776             </TR>
 777             <TR>
 778                 <TD>
 779                 </TD>
 780                 <TD>
 781                     <STRONG>Windows NT:&nbsp;</STRONG> <CODE>FastCgiIpcDir <EM>name</EM></CODE>
 782                 </TD>
 783             </TR>
 784             <TR>
 785                 <TD>
 786                     <A HREF=
 787                     "http://httpd.apache.org/docs/mod/directive-dict.html#Default"><STRONG>Default:</STRONG></A>
 788                 </TD>
 789                 <TD>
 790                     <STRONG>Unix:&nbsp;</STRONG> <CODE>FastCgiIpcDir /tmp/fcgi</CODE>
 791                 </TD>
 792             </TR>
 793             <TR>
 794                 <TD>
 795                 </TD>
 796                 <TD>
 797                     <STRONG>Windows NT:&nbsp;</STRONG> <CODE>FastCgiIpcDir \\.\pipe\ModFastCgi\</CODE>
 798                 </TD>
 799             </TR>
 800             <TR>
 801                 <TD>
 802                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
 803                     "Help"><STRONG>Context:</STRONG></A>
 804                 </TD>
 805                 <TD>
 806                     server config
 807                 </TD>
 808             </TR>
 809         </TABLE>
 810         <P>
 811             <STRONG>Unix:&nbsp;</STRONG> The <CODE>FastCgiIpcDir</CODE> directive specifies <EM>directory</EM> as the
 812             place to store (and in the case of external FastCGI applications, find) the Unix socket files used for
 813             communication between the applications and the web server. If the directory does not begin with a slash (/)
 814             then it is assumed to be relative to the <A HREF=
 815             "http://httpd.apache.org/docs/mod/core.html#serverroot">ServerRoot</A>. If the directory doesn&#39;t exist,
 816             an attempt is made to create it with appropriate permissions. Do not specify a directory that is not on a
 817             local filesystem! If you use the default directory (or another directory within <CODE>/tmp</CODE>),
 818             <CODE>mod_fastcgi</CODE> will break if your system periodically deletes files from <CODE>/tmp</CODE>.
 819         </P>
 820         <P>
 821             <STRONG>Windows NT:&nbsp;</STRONG> The <CODE>FastCgiIpcDir</CODE> directive specifies <EM>name</EM> as the
 822             root for the named pipes used for communication between the application and the web server. The
 823             <EM>name</EM> must be in the form of <STRONG>\\.\pipe\</STRONG><EM>pipename.</EM> The <EM>pipename</EM>
 824             part can contain any character other than a backslash
 825         </P>
 826         <P>
 827             The <CODE>FastCgiIpcDir</CODE> directive must precede any <A HREF=
 828             "#FastCgiServer"><CODE>FastCgiServer</CODE></A> or <A HREF=
 829             "#FastCgiExternalServer"><CODE>FastCgiExternalServer</CODE></A> directives (which make use of Unix
 830             sockets). The directory must be readable, writeable, and executable (searchable) by the web server, but
 831             otherwise should not be accessible to anyone.
 832         </P>
 833         <HR>
 834         <H2>
 835             <A NAME="FastCgiWrapper">FastCgiWrapper</A>
 836         </H2>
 837         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
 838         <TABLE BORDER="0" SUMMARY="">
 839             <TR>
 840                 <TD>
 841                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
 842                     "Help"><STRONG>Syntax:</STRONG></A>
 843                 </TD>
 844                 <TD>
 845                     <CODE>FastCgiWrapper <EM>On | Off | filename</EM></CODE>
 846                 </TD>
 847             </TR>
 848             <TR>
 849                 <TD>
 850                     <A HREF=
 851                     "http://httpd.apache.org/docs/mod/directive-dict.html#Default"><STRONG>Default:</STRONG></A>
 852                 </TD>
 853                 <TD>
 854                     <CODE>FastCgiWrapper Off</CODE>
 855                 </TD>
 856             </TR>
 857             <TR>
 858                 <TD>
 859                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
 860                     "Help"><STRONG>Context:</STRONG></A>
 861                 </TD>
 862                 <TD>
 863                     server config
 864                 </TD>
 865             </TR>
 866         </TABLE>
 867         <P>
 868             The <CODE>FastCgiWrapper</CODE> directive is used to enable support for a wrapper such as <A HREF=
 869             "http://httpd.apache.org/docs/suexec.html">suexec</A> (included with Apache in the support directory) or <A
 870             HREF="http://cgiwrap.sourceforge.net/">cgiwrap</A>. To use the same wrapper used by Apache, set
 871             <CODE>FastCgiWrapper</CODE> to <EM>On</EM> (NOTE - mod_fastcgi cannot reliably determine the wrapper used
 872             by Apache when built as a DSO). The <EM>On</EM> argument requires suexec be enabled in Apache (for CGI). To
 873             use a specific wrapper, specify a <EM>filename</EM>. If the filename does not begin with a slash (/) then
 874             it is assumed to be relative to the <A HREF=
 875             "http://httpd.apache.org/docs/mod/core.html#serverroot">ServerRoot</A>. The wrapper is used to invoke all
 876             FastCGI applications (in the future this directive will have directory context).
 877         </P>
 878         <P>
 879             When <CODE>FastCgiWrapper</CODE> is enabled, no assumptions are made about the target application and thus
 880             presence and permissions checks cannot be made. This is the responsibility of the wrapper.
 881         </P>
 882         <P>
 883             The wrapper is invoked with the following arguments: username, group, application. The username and group
 884             are determined as described below. The application is the &quot;filename&quot; Apache resolves the
 885             requested URI to (dynamic) or the filename provided as an argument to another FastCGI (server or
 886             authorizer) directive. These arguments may or may not be used by the wrapper (e.g. suexec uses them,
 887             cgiwrap parses the URI and ignores them). The environment passed to the wrapper is identical to the
 888             environment passed when a wrapper is not in use.
 889         </P>
 890         <P>
 891             When <CODE>FastCgiWrapper</CODE> is enabled, the location of static or external FastCGI application
 892             directives can be important. They inherit their user and group from the <CODE>User</CODE> and
 893             <CODE>Group</CODE> of the virtual server in which they were defined. <CODE>User</CODE> and
 894             <CODE>Group</CODE> directives should precede FastCGI application definitions. Note that this does
 895             <EM>not</EM> limit the FastCGI application to the virtual server in which they were defined, the
 896             application is allowed to service requests from any virtual server with the same user and group. If a
 897             request is received for a FastCGI application without an existing matching definition running with the
 898             correct user and group, a dynamic instance of the application is started with the correct user and group.
 899             This can lead to multiple copies of the same application running with different user/group. If this is a
 900             problem, preclude navigation to the application from other virtual servers or configure the virtual servers
 901             with the same User and Group.
 902         </P>
 903         <P>
 904             See the Apache documentation for more information about suexec (make sure you fully understand the security
 905             implications).
 906         </P>
 907         <HR>
 908         <H2>
 909             <A NAME="FastCgiAuthenticator">FastCgiAuthenticator</A>
 910         </H2>
 911         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
 912         <TABLE BORDER="0" SUMMARY="">
 913             <TR>
 914                 <TD>
 915                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
 916                     "Help"><STRONG>Syntax:</STRONG></A>
 917                 </TD>
 918                 <TD>
 919                     <CODE>FastCgiAuthenticator <EM>filename</EM> [-compat]</CODE>
 920                 </TD>
 921             </TR>
 922             <TR>
 923                 <TD>
 924                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
 925                     "Help"><STRONG>Context:</STRONG></A>
 926                 </TD>
 927                 <TD>
 928                     directory
 929                 </TD>
 930             </TR>
 931         </TABLE>
 932         <P>
 933             The <CODE>FastCgiAuthenticator</CODE> directive is used to define a FastCGI application as a per-directory
 934             authenticator. Authenticators verify the requestor is who he says he is by matching the provided username
 935             and password against a list or database of known users and passwords. FastCGI based authenticators are
 936             useful primarily when the user database is maintained within an existing independent program or resides on
 937             a machine other than the web server.
 938         </P>
 939         <P>
 940             If the FastCGI application <EM>filename</EM> does not have a corresponding static or external server
 941             definition, it is started as a dynamic FastCGI application. If the filename does not begin with a slash (/)
 942             then it is assumed to be relative to the <A HREF=
 943             "http://httpd.apache.org/docs/mod/core.html#serverroot">ServerRoot</A>.
 944         </P>
 945         <P>
 946             <CODE>FastCgiAuthenticator</CODE> is used within <A HREF=
 947             "http://httpd.apache.org/docs/mod/core.html#directory"><CODE>Directory</CODE></A> or <A HREF=
 948             "http://httpd.apache.org/docs/mod/core.html#location"><CODE>Location</CODE></A> containers and must include
 949             an <A HREF="http://httpd.apache.org/docs/mod/core.html#authtype"><CODE>AuthType</CODE></A> and <A HREF=
 950             "http://httpd.apache.org/docs/mod/core.html#authname"><CODE>AuthName</CODE></A> directive. Only the
 951             <CODE>Basic</CODE> user authentication type is supported. It must be accompanied by a <A HREF=
 952             "http://httpd.apache.org/docs/mod/core.html#require"><CODE>require</CODE></A> or <CODE><A HREF=
 953             "#FastCgiAuthorizer">FastCgiAuthorizer</A></CODE> directive in order to work correctly.
 954         </P>
 955         <BLOCKQUOTE>
 956 <PRE>
 957 &lt;Directory htdocs/protected&gt;
 958     AuthType Basic
 959     AuthName ProtectedRealm
 960     FastCgiAuthenticator fcgi-bin/authenticator
 961     require valid-user
 962 &lt;/Directory&gt;
 963 </PRE>
 964         </BLOCKQUOTE>
 965         <P>
 966             <CODE>mod_fastcgi</CODE> sends nearly all of the standard environment variables typically available to
 967             CGI/FastCGI request handlers. All headers returned by a FastCGI authentication application in a successful
 968             response (Status: 200) are passed to sub-processes (CGI/FastCGI invocations) as environment variables. All
 969             headers returned in an unsuccessful response are passed on to the client. FastCGI specification compliant
 970             behavior can be obtained by using the <CODE>-compat</CODE> option.
 971         </P>
 972         <P>
 973             <CODE>mod_fastcgi</CODE> sets the environment variable &quot;FCGI_APACHE_ROLE&quot; to
 974             &quot;AUTHENTICATOR&quot; to indicate which (Apache specific) authorizer phase is being performed.
 975         </P>
 976         <P>
 977             Custom failure responses from FastCGI authorizer applications are not (yet?) supported. See the <A HREF=
 978             "http://httpd.apache.org/docs/mod/core.html#errordocument">ErrorDocument</A> directive for a workaround (a
 979             FastCGI application can serve the document).
 980         </P>
 981         <HR>
 982         <H2>
 983             <A NAME="FastCgiAuthenticatorAuthoritative">FastCgiAuthenticatorAuthoritative</A>
 984         </H2>
 985         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
 986         <TABLE BORDER="0" SUMMARY="">
 987             <TR>
 988                 <TD>
 989                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
 990                     "Help"><STRONG>Syntax:</STRONG></A>
 991                 </TD>
 992                 <TD>
 993                     <CODE>FastCgiAuthenticatorAuthoritative <EM>On | Off</EM></CODE>
 994                 </TD>
 995             </TR>
 996             <TR>
 997                 <TD>
 998                     <A HREF=
 999                     "http://httpd.apache.org/docs/mod/directive-dict.html#Default"><STRONG>Default:</STRONG></A>
1000                 </TD>
1001                 <TD>
1002                     <CODE>FastCgiAuthenticatorAuthoritative On</CODE>
1003                 </TD>
1004             </TR>
1005             <TR>
1006                 <TD>
1007                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
1008                     "Help"><STRONG>Context:</STRONG></A>
1009                 </TD>
1010                 <TD>
1011                     directory
1012                 </TD>
1013             </TR>
1014         </TABLE>
1015         <P>
1016             Setting the <CODE>FastCgiAuthenticatorAuthoritative</CODE> directive explicitly to <EM>Off</EM> allows
1017             authentication to be passed on to lower level modules (as defined in the <CODE>Configuration</CODE> and
1018             <CODE>modules.c</CODE> files) if the FastCGI application fails to authenticate the user.
1019         </P>
1020         <P>
1021             A common use for this is in conjunction with a well protected <A HREF=
1022             "http://httpd.apache.org/docs/mod/mod_auth.html#authuserfile"><CODE>AuthUserFile</CODE></A> containing a
1023             few (administration related) users.
1024         </P>
1025         <P>
1026             By default, control is not passed on and an unknown user will result in an Authorization Required reply.
1027             Disabling the default should be carefully considered.
1028         </P>
1029         <HR>
1030         <H2>
1031             <A NAME="FastCgiAuthorizer">FastCgiAuthorizer</A>
1032         </H2>
1033         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
1034         <TABLE BORDER="0" SUMMARY="">
1035             <TR>
1036                 <TD>
1037                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
1038                     "Help"><STRONG>Syntax:</STRONG></A>
1039                 </TD>
1040                 <TD>
1041                     <CODE>FastCgiAuthorizer <EM>filename</EM> [-compat]</CODE>
1042                 </TD>
1043             </TR>
1044             <TR>
1045                 <TD>
1046                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
1047                     "Help"><STRONG>Context:</STRONG></A>
1048                 </TD>
1049                 <TD>
1050                     directory
1051                 </TD>
1052             </TR>
1053         </TABLE>
1054         <P>
1055             The <CODE>FastCgiAuthorizer</CODE> directive is used to define a FastCGI application as a per-directory
1056             authorizer. Authorizers validate whether an authenticated requestor is allowed access to the requested
1057             resource. FastCGI based authorizers are useful primarily when there is a dynamic component to the
1058             authorization decision such as a time of day or whether or not the user has paid his bills.
1059         </P>
1060         <P>
1061             If the FastCGI application <EM>filename</EM> does not have a corresponding static or external server
1062             definition, it is started as a dynamic FastCGI application. If the filename does not begin with a slash (/)
1063             then it is assumed to be relative to the <A HREF=
1064             "http://httpd.apache.org/docs/mod/core.html#serverroot">ServerRoot</A>.
1065         </P>
1066         <P>
1067             <CODE>FastCgiAuthorizer</CODE> is used within <A HREF=
1068             "http://httpd.apache.org/docs/mod/core.html#directory"><CODE>Directory</CODE></A> or <A HREF=
1069             "http://httpd.apache.org/docs/mod/core.html#location"><CODE>Location</CODE></A> containers and must include
1070             an <A HREF="http://httpd.apache.org/docs/mod/core.html#authtype"><CODE>AuthType</CODE></A> and <A HREF=
1071             "http://httpd.apache.org/docs/mod/core.html#authname"><CODE>AuthName</CODE></A> directive. It must be
1072             accompanied by an authentication directive such as <A HREF=
1073             "#FastCgiAuthenticator"><CODE>FastCgiAuthenticator</CODE></A>, <A HREF=
1074             "http://httpd.apache.org/docs/mod/mod_auth.html#authuserfile"><CODE>AuthUserFile</CODE></A>, <A HREF=
1075             "http://httpd.apache.org/docs/mod/mod_auth_db.html#authdbuserfile"><CODE>AuthDBUserFile</CODE></A> or <A
1076             HREF="http://httpd.apache.org/docs/mod/mod_auth_dbm.html#authdbmuserfile"><CODE>AuthDBMUserFile</CODE></A>
1077             in order to work correctly.
1078         </P>
1079         <BLOCKQUOTE>
1080 <PRE>
1081 &lt;Directory htdocs/protected&gt;
1082     AuthType Basic
1083     AuthName ProtectedRealm
1084     AuthDBMUserFile conf/authentication-database
1085     FastCgiAuthorizer fcgi-bin/authorizer
1086 &lt;/Directory&gt;
1087 </PRE>
1088         </BLOCKQUOTE>
1089         <P>
1090             <CODE>mod_fastcgi</CODE> sends nearly all of the standard environment variables typically available to
1091             CGI/FastCGI request handlers. All headers returned by a FastCGI authorizer application in a successful
1092             response (Status: 200) are passed to sub-processes (CGI/FastCGI invocations) as environment variables. All
1093             headers returned in an unsuccessful response are passed on to the client. FastCGI specification compliant
1094             behavior can be obtained by using the <CODE>-compat</CODE> option.
1095         </P>
1096         <P>
1097             <CODE>mod_fastcgi</CODE> sets the environment variable &quot;FCGI_APACHE_ROLE&quot; to
1098             &quot;AUTHORIZER&quot; to indicate which (Apache specific) authorizer phase is being performed.
1099         </P>
1100         <P>
1101             Custom failure responses from FastCGI authorizer applications are not (yet?) supported. See the <A HREF=
1102             "http://httpd.apache.org/docs/mod/core.html#errordocument">ErrorDocument</A> directive for a workaround (a
1103             FastCGI application can serve the document).
1104         </P>
1105         <HR>
1106         <H2>
1107             <A NAME="FastCgiAuthorizerAuthoritative">FastCgiAuthorizerAuthoritative</A>
1108         </H2>
1109         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
1110         <TABLE BORDER="0" SUMMARY="">
1111             <TR>
1112                 <TD>
1113                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
1114                     "Help"><STRONG>Syntax:</STRONG></A>
1115                 </TD>
1116                 <TD>
1117                     <CODE>FastCgiAuthorizerAuthoritative <EM>On | Off</EM></CODE>
1118                 </TD>
1119             </TR>
1120             <TR>
1121                 <TD>
1122                     <A HREF=
1123                     "http://httpd.apache.org/docs/mod/directive-dict.html#Default"><STRONG>Default:</STRONG></A>
1124                 </TD>
1125                 <TD>
1126                     <CODE>FastCgiAuthorizerAuthoritative On</CODE>
1127                 </TD>
1128             </TR>
1129             <TR>
1130                 <TD>
1131                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
1132                     "Help"><STRONG>Context:</STRONG></A>
1133                 </TD>
1134                 <TD>
1135                     directory
1136                 </TD>
1137             </TR>
1138         </TABLE>
1139         <P>
1140             Setting the <CODE>FastCgiAuthorizerAuthoritative</CODE> directive explicitly to <EM>Off</EM> allows
1141             authorization to be passed on to lower level modules (as defined in the <CODE>Configuration</CODE> and
1142             <CODE>modules.c</CODE> files) if the FastCGI application fails to authorize the user.
1143         </P>
1144         <P>
1145             By default, control is not passed on and an unauthorized user will result in an Authorization Required
1146             reply. Disabling the default should be carefully considered.
1147         </P>
1148         <HR>
1149         <H2>
1150             <A NAME="FastCgiAccessChecker">FastCgiAccessChecker</A>
1151         </H2>
1152         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
1153         <TABLE BORDER="0" SUMMARY="">
1154             <TR>
1155                 <TD>
1156                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
1157                     "Help"><STRONG>Syntax:</STRONG></A>
1158                 </TD>
1159                 <TD>
1160                     <CODE>FastCgiAccessChecker <EM>filename</EM> [-compat]</CODE>
1161                 </TD>
1162             </TR>
1163             <TR>
1164                 <TD>
1165                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
1166                     "Help"><STRONG>Context:</STRONG></A>
1167                 </TD>
1168                 <TD>
1169                     directory
1170                 </TD>
1171             </TR>
1172         </TABLE>
1173         <P>
1174             The <CODE>FastCgiAccessChecker</CODE> (suggestions for a better name are welcome) directive is used to
1175             define a FastCGI application as a per-directory access validator. The Apache Access phase precede user
1176             authentication and thus the decision to (dis)allow access to the requested resource is based on the HTTP
1177             headers submitted with the request. FastCGI based authorizers are useful primarily when there is a dynamic
1178             component to the access validation decision such as a time of day or whether or not a domain has paid his
1179             bills.
1180         </P>
1181         <P>
1182             If the FastCGI application <EM>filename</EM> does not have a corresponding static or external server
1183             definition, it is started as a dynamic FastCGI application. If the filename does not begin with a slash (/)
1184             then it is assumed to be relative to the <A HREF=
1185             "http://httpd.apache.org/docs/mod/core.html#serverroot">ServerRoot</A>.
1186         </P>
1187         <P>
1188             <CODE>FastCgiAccessChecker</CODE> is used within <A HREF=
1189             "http://httpd.apache.org/docs/mod/core.html#directory"><CODE>Directory</CODE></A> or <A HREF=
1190             "http://httpd.apache.org/docs/mod/core.html#location"><CODE>Location</CODE></A> containers.
1191         </P>
1192         <BLOCKQUOTE>
1193 <PRE>
1194 &lt;Directory htdocs/protected&gt;
1195     FastCgiAccessChecker fcgi-bin/access-checker
1196 &lt;/Directory&gt;
1197 </PRE>
1198         </BLOCKQUOTE>
1199         <P>
1200             <CODE>mod_fastcgi</CODE> sends nearly all of the standard environment variables typically available to
1201             CGI/FastCGI request handlers. All headers returned by a FastCGI access-checker application in a successful
1202             response (Status: 200) are passed to sub-processes (CGI/FastCGI invocations) as environment variables. All
1203             headers returned in an unsuccessful response are passed on to the client. FastCGI specification compliant
1204             behavior can be obtained by using the <CODE>-compat</CODE> option.
1205         </P>
1206         <P>
1207             <CODE>mod_fastcgi</CODE> sets the environment variable &quot;FCGI_APACHE_ROLE&quot; to
1208             &quot;ACCESS_CHECKER&quot; to indicate which (Apache specific) authorizer phase is being performed.
1209         </P>
1210         <P>
1211             Custom failure responses from FastCGI authorizer applications are not (yet?) supported. See the <A HREF=
1212             "http://httpd.apache.org/docs/mod/core.html#errordocument">ErrorDocument</A> directive for a workaround (a
1213             FastCGI application can serve the document).
1214         </P>
1215         <HR>
1216         <H2>
1217             <A NAME="FastCgiAccessCheckerAuthoritative">FastCgiAccessCheckerAuthoritative</A>
1218         </H2>
1219         <!-- %plaintext &lt;?INDEX {\tt FastCgiConfig} directive&gt; -->
1220         <TABLE BORDER="0" SUMMARY="">
1221             <TR>
1222                 <TD>
1223                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Syntax" REL=
1224                     "Help"><STRONG>Syntax:</STRONG></A>
1225                 </TD>
1226                 <TD>
1227                     <CODE>FastCgiAccessCheckerAuthoritative <EM>On | Off</EM></CODE>
1228                 </TD>
1229             </TR>
1230             <TR>
1231                 <TD>
1232                     <A HREF=
1233                     "http://httpd.apache.org/docs/mod/directive-dict.html#Default"><STRONG>Default:</STRONG></A>
1234                 </TD>
1235                 <TD>
1236                     <CODE>FastCgiAccessCheckerAuthoritative On</CODE>
1237                 </TD>
1238             </TR>
1239             <TR>
1240                 <TD>
1241                     <A HREF="http://httpd.apache.org/docs/mod/directive-dict.html#Context" REL=
1242                     "Help"><STRONG>Context:</STRONG></A>
1243                 </TD>
1244                 <TD>
1245                     directory
1246                 </TD>
1247             </TR>
1248         </TABLE>
1249         <P>
1250             Setting the <CODE>FastCgiAccessCheckerAuthoritative</CODE> directive explicitly to <EM>Off</EM> allows
1251             access checking to be passed on to lower level modules (as defined in the <CODE>Configuration</CODE> and
1252             <CODE>modules.c</CODE> files) if the FastCGI application fails to allow access.
1253         </P>
1254         <P>
1255             By default, control is not passed on and a failed access check will result in a Forbidden reply. Disabling
1256             the default should be carefully considered.
1257         </P>
1258         <HR>
1259         <H3 CLASS="c3">
1260             <A HREF="http://www.FastCGI.com/">www.FastCGI.com</A>
1261         </H3>
1262     </BODY>
1263 </HTML>
1264