summaryrefslogtreecommitdiffstats
path: root/docs/manual/platform/ebcdic.html.en
blob: 01b95c8dc5cde1c37429b7a69f9761351c7edc6c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head>
<meta content="text/html; charset=UTF-8" http-equiv="Content-Type" />
<!--
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
              This file is generated from xml source: DO NOT EDIT
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
      -->
<title>The Apache EBCDIC Port - Apache HTTP Server Version 2.4</title>
<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /><link rel="stylesheet" type="text/css" href="../style/css/prettify.css" />
<script src="../style/scripts/prettify.min.js" type="text/javascript">
</script>

<link href="../images/favicon.ico" rel="shortcut icon" /></head>
<body id="manual-page"><div id="page-header">
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
<p class="apache">Apache HTTP Server Version 2.4</p>
<img alt="" src="../images/feather.png" /></div>
<div class="up"><a href="./"><img title="&lt;-" alt="&lt;-" src="../images/left.gif" /></a></div>
<div id="path">
<a href="http://www.apache.org/">Apache</a> &gt; <a href="http://httpd.apache.org/">HTTP Server</a> &gt; <a href="http://httpd.apache.org/docs/">Documentation</a> &gt; <a href="../">Version 2.4</a> &gt; <a href="./">Platform Specific Notes</a></div><div id="page-content"><div id="preamble"><h1>The Apache EBCDIC Port</h1>
<div class="toplang">
<p><span>Available Languages: </span><a href="../en/platform/ebcdic.html" title="English">&nbsp;en&nbsp;</a> |
<a href="../ko/platform/ebcdic.html" hreflang="ko" rel="alternate" title="Korean">&nbsp;ko&nbsp;</a></p>
</div>


    <div class="warning"><strong>Warning:</strong> This document
    has not been updated to take into account changes made in
    the 2.0 version of the Apache HTTP Server. Some of the
    information may still be relevant, but please use it with care.
    </div>

  </div>
<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#overview">Overview of the Apache EBCDIC Port</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#design">Design Goals</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#technical">Technical Solution</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#porting">Porting Notes</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#document">Document Storage Notes</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#modules">Apache Modules' Status</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#third-party">Third Party Modules' Status</a></li>
</ul><h3>See also</h3><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="overview" id="overview">Overview of the Apache EBCDIC Port</a></h2>

    

    <p>Version 1.3 of the Apache HTTP Server was the first version
    which included a port to a (non-ASCII) mainframe machine which
    uses the EBCDIC character set as its native codeset.</p>

    <p>(It is the SIEMENS family of mainframes running the <a href="http://www.siemens.de/servers/bs2osd/osdbc_us.htm">BS2000/OSD
    operating system</a>. This mainframe OS nowadays features a
    SVR4-derived POSIX subsystem).</p>

    <p>The port was started initially to</p>

    <ul>
      <li>prove the feasibility of porting <a href="http://httpd.apache.org/">the Apache HTTP server</a> to
      this platform</li>

      <li>find a "worthy and capable" successor for the venerable
      <a href="http://www.w3.org/Daemon/">CERN-3.0</a> daemon
      (which was ported a couple of years ago), and to</li>

      <li>prove that Apache's preforking process model can on this
      platform easily outperform the accept-fork-serve model used
      by CERN by a factor of 5 or more.</li>
    </ul>

    <p>This document serves as a rationale to describe some of the
    design decisions of the port to this machine.</p>

  </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="design" id="design">Design Goals</a></h2>

    

    <p>One objective of the EBCDIC port was to maintain enough
    backwards compatibility with the (EBCDIC) CERN server to make
    the transition to the new server attractive and easy. This
    required the addition of a configurable method to define
    whether a HTML document was stored in ASCII (the only format
    accepted by the old server) or in EBCDIC (the native document
    format in the POSIX subsystem, and therefore the only realistic
    format in which the other POSIX tools like <code>grep</code> or
    <code>sed</code> could operate on the documents). The current
    solution to this is a "pseudo-MIME-format" which is intercepted
    and interpreted by the Apache server (see below). Future versions
    might solve the problem by defining an "ebcdic-handler" for all
    documents which must be converted.</p>

  </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="technical" id="technical">Technical Solution</a></h2>

    

    <p>Since all Apache input and output is based upon the BUFF
    data type and its methods, the easiest solution was to add the
    conversion to the BUFF handling routines. The conversion must
    be settable at any time, so a BUFF flag was added which defines
    whether a BUFF object has currently enabled conversion or not.
    This flag is modified at several points in the HTTP
    protocol:</p>

    <ul>
      <li><strong>set</strong> before a request is received
      (because the request and the request header lines are always
      in ASCII format)</li>

      <li><strong>set/unset</strong> when the request body is
      received - depending on the content type of the request body
      (because the request body may contain ASCII text or a binary
      file)</li>

      <li><strong>set</strong> before a reply header is sent
      (because the response header lines are always in ASCII
      format)</li>

      <li><strong>set/unset</strong> when the response body is sent
      - depending on the content type of the response body (because
      the response body may contain text or a binary file)</li>
    </ul>

  </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="porting" id="porting">Porting Notes</a></h2>

    

    <ol>
      <li>
        <p>The relevant changes in the source are <code>#ifdef</code>'ed
        into two categories:</p>

        <dl>
          <dt><code><strong>#ifdef
          CHARSET_EBCDIC</strong></code></dt>

          <dd>
            <p>Code which is needed for any EBCDIC based machine.
            This includes character translations, differences in
            contiguity of the two character sets, flags which
            indicate which part of the HTTP protocol has to be
            converted and which part doesn't <em>etc.</em></p>
          </dd>

          <dt><code><strong>#ifdef _OSD_POSIX</strong></code></dt>

          <dd>
            <p>Code which is needed for the SIEMENS BS2000/OSD
            mainframe platform only. This deals with include file
            differences and socket implementation topics which are
            only required on the BS2000/OSD platform.</p>
          </dd>
        </dl>
      </li>

      <li>
        <p>The possibility to translate between ASCII and EBCDIC at
        the socket level (on BS2000 POSIX, there is a socket option
        which supports this) was intentionally <em>not</em> chosen,
        because the byte stream at the HTTP protocol level consists
        of a mixture of protocol related strings and non-protocol
        related raw file data. HTTP protocol strings are always
        encoded in ASCII (the <code>GET</code> request, any Header: lines,
        the chunking information <em>etc.</em>) whereas the file transfer
        parts (<em>i.e.</em>, GIF images, CGI output <em>etc.</em>)
        should usually be just "passed through" by the server. This
        separation between "protocol string" and "raw data" is
        reflected in the server code by functions like <code>bgets()</code>
        or <code>rvputs()</code> for strings, and functions like
        <code>bwrite()</code> for binary data. A global translation
        of everything would therefore be inadequate.</p>

        <p>(In the case of text files of course, provisions must be
        made so that EBCDIC documents are always served in
        ASCII)</p>
      </li>

      <li>
        <p>This port therefore features a built-in protocol level
        conversion for the server-internal strings (which the
        compiler translated to EBCDIC strings) and thus for all
        server-generated documents. The hard coded ASCII escapes
        <code>\012</code> and <code>\015</code> which are ubiquitous
        in the server code are an exception: they are already the binary
        encoding of the ASCII <code>\n</code> and <code>\r</code> and
        must not be converted to ASCII a second time.
        This exception is only relevant for server-generated strings;
        and <em>external</em> EBCDIC documents are not expected to
        contain ASCII newline characters.</p>
      </li>

      <li>
        <p>By examining the call hierarchy for the BUFF management
        routines, I added an "ebcdic/ascii conversion layer" which
        would be crossed on every puts/write/get/gets, and a
        conversion flag which allowed enabling/disabling the
        conversions on-the-fly. Usually, a document crosses this
        layer twice from its origin source (a file or CGI output) to
        its destination (the requesting client): <code>file -&gt;
        Apache</code>, and <code>Apache -&gt; client</code>.</p>

        <p>The server can now read the header lines of a CGI-script
        output in EBCDIC format, and then find out that the remainder
        of the script's output is in ASCII (like in the case of the
        output of a WWW Counter program: the document body contains a
        GIF image). All header processing is done in the native
        EBCDIC format; the server then determines, based on the type
        of document being served, whether the document body (except
        for the chunking information, of course) is in ASCII already
        or must be converted from EBCDIC.</p>
      </li>

      <li>
        <p>For Text documents (MIME types text/plain, text/html
        <em>etc.</em>), an implicit translation to ASCII can be
        used, or (if the users prefer to store some documents in
        raw ASCII form for faster serving, or because the files
        reside on a NFS-mounted directory tree) can be served
        without conversion.</p>

        <p><strong>Example:</strong></p>

        <p>to serve files with the suffix <code>.ahtml</code> as a
        raw ASCII <code>text/html</code> document without implicit
        conversion (and suffix <code>.ascii</code> as ASCII
        <code>text/plain</code>), use the directives:</p>

        <div class="example"><p><code>
          AddType  text/x-ascii-html  .ahtml <br />
          AddType  text/x-ascii-plain .ascii
        </code></p></div>

        <p>Similarly, any <code>text/foo</code> MIME type can be
        served as "raw ASCII" by configuring a MIME type
        "<code>text/x-ascii-foo</code>" for it using
        <code>AddType</code>.</p>
      </li>

      <li>
        <p>Non-text documents are always served "binary" without
        conversion. This seems to be the most sensible choice for,
        .<em>e.g.</em>, GIF/ZIP/AU file types. This of course
        requires the user to copy them to the mainframe host using
        the "<code>rcp -b</code>" binary switch.</p>
      </li>

      <li>
        <p>Server parsed files are always assumed to be in native
        (<em>i.e.</em>, EBCDIC) format as used on the machine, and
        are converted after processing.</p>
      </li>

      <li>
        <p>For CGI output, the CGI script determines whether a
        conversion is needed or not: by setting the appropriate
        Content-Type, text files can be converted, or GIF output can
        be passed through unmodified. An example for the latter case
        is the wwwcount program which we ported as well.</p>
      </li>

    </ol>

  </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="document" id="document">Document Storage Notes</a></h2>

    

    <h3><a name="binary" id="binary">Binary Files</a></h3>

      

      <p>All files with a <code>Content-Type:</code> which does not
      start with <code>text/</code> are regarded as <em>binary
      files</em> by the server and are not subject to any conversion.
      Examples for binary files are GIF images, gzip-compressed files
      and the like.</p>

      <p>When exchanging binary files between the mainframe host and
      a Unix machine or Windows PC, be sure to use the ftp "binary"
      (<code>TYPE I</code>) command, or use the
      <code>rcp -b</code> command from the mainframe host (the
      <code>-b</code> switch is not supported in unix
      <code>rcp</code>'s).</p>

    

    <h3><a name="text" id="text">Text Documents</a></h3>

      

      <p>The default assumption of the server is that Text Files
      (<em>i.e.</em>, all files whose <code>Content-Type:</code>
      starts with <code>text/</code>) are stored in the native
      character set of the host, EBCDIC.</p>

    

    <h3><a name="ssi" id="ssi">Server Side Included Documents</a></h3>

      

      <p>SSI documents must currently be stored in EBCDIC only.
      No provision is made to convert it from ASCII before
      processing.</p>

    

  </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="modules" id="modules">Apache Modules' Status</a></h2>

    

    <table class="bordered">
      <tr>
        <th>Module</th>
        <th>Status</th>
        <th>Notes</th>
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/core.html">core</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module">mod_access</code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_actions.html">mod_actions</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_alias.html">mod_alias</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_asis.html">mod_asis</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module">mod_auth</code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_authn_anon.html">mod_authn_anon</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_authn_dbm.html">mod_authn_dbm</a></code></td>
        <td class="centered">?</td>
        <td>with own <code>libdb.a</code></td>
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_authz_dbm.html">mod_authz_dbm</a></code></td>
        <td class="centered">?</td>
        <td>with own <code>libdb.a</code></td>
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_autoindex.html">mod_autoindex</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_cern_meta.html">mod_cern_meta</a></code></td>
        <td class="centered">?</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_cgi.html">mod_cgi</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code>mod_digest</code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_dir.html">mod_dir</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_so.html">mod_so</a></code></td>
        <td class="centered">-</td>
        <td>no shared libs</td>
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_env.html">mod_env</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_example.html">mod_example</a></code></td>
        <td class="centered">-</td>
        <td>(test bed only)</td>
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_expires.html">mod_expires</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_headers.html">mod_headers</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_imagemap.html">mod_imagemap</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_include.html">mod_include</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_info.html">mod_info</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code>mod_log_agent</code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code>mod_log_config</code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module">mod_log_referer</code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_mime.html">mod_mime</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_mime_magic.html">mod_mime_magic</a></code></td>
        <td class="centered">?</td>
        <td>not ported yet</td>
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_negotiation.html">mod_negotiation</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code></td>
        <td class="centered">+</td>
        <td>untested</td>
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_setenvif.html">mod_setenvif</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_speling.html">mod_speling</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_status.html">mod_status</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_unique_id.html">mod_unique_id</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_userdir.html">mod_userdir</a></code></td>
        <td class="centered">+</td>
        <td />
      </tr>

      <tr>
        <td><code class="module"><a href="../mod/mod_usertrack.html">mod_usertrack</a></code></td>
        <td class="centered">?</td>
        <td>untested</td>
      </tr>
    </table>

  </div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="third-party" id="third-party">Third Party Modules' Status</a></h2>

    

    <table class="bordered">
      <tr>
        <th>Module</th>
        <th>Status</th>
        <th>Notes</th>
      </tr>

      <tr>
        <td><code><a href="https://tomcat.apache.org/connectors-doc-archive/jk2/">JK</a> (Formerly mod_jserv)
        </code></td>
        <td class="centered">-</td>
        <td>JAVA still being ported.</td>
      </tr>

      <tr>
        <td><code><a href="http://www.php.net/">mod_php3</a></code></td>
        <td class="centered">+</td>
        <td><code>mod_php3</code> runs fine, with LDAP and GD
        and FreeType libraries.</td>
      </tr>

      <tr>
        <td><code><a href="http://hpwww.ec-lyon.fr/~vincent/apache/mod_put.html">mod_put</a></code></td>
        <td class="centered">?</td>
        <td>untested</td>
      </tr>

      <tr>
        <td><code><a href="ftp://hachiman.vidya.com/pub/apache/">mod_session</a></code></td>
        <td class="centered">-</td>
        <td>untested</td>
      </tr>
    </table>

  </div></div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="../en/platform/ebcdic.html" title="English">&nbsp;en&nbsp;</a> |
<a href="../ko/platform/ebcdic.html" hreflang="ko" rel="alternate" title="Korean">&nbsp;ko&nbsp;</a></p>
</div><div class="top"><a href="#page-header"><img src="../images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&amp;A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed by our moderators if they are either implemented or considered invalid/off-topic. Questions on how to manage the Apache HTTP Server should be directed at either our IRC channel, #httpd, on Libera.chat, or sent to our <a href="https://httpd.apache.org/lists.html">mailing lists</a>.</div>
<script type="text/javascript"><!--//--><![CDATA[//><!--
var comments_shortname = 'httpd';
var comments_identifier = 'http://httpd.apache.org/docs/2.4/platform/ebcdic.html';
(function(w, d) {
    if (w.location.hostname.toLowerCase() == "httpd.apache.org") {
        d.write('<div id="comments_thread"><\/div>');
        var s = d.createElement('script');
        s.type = 'text/javascript';
        s.async = true;
        s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier;
        (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s);
    }
    else { 
        d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>');
    }
})(window, document);
//--><!]]></script></div><div id="footer">
<p class="apache">Copyright 2023 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p>
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div><script type="text/javascript"><!--//--><![CDATA[//><!--
if (typeof(prettyPrint) !== 'undefined') {
    prettyPrint();
}
//--><!]]></script>
</body></html>