Initial commit

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diff --git a/.gitignore b/.gitignore
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+++ b/.gitignore
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+index.html
+*~
+.emacs*
+.cache
diff --git a/Makefile b/Makefile
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+++ b/Makefile
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+CVSREPO=:ext:gray@puszcza.gnu.org.ua:/webcvs/xenv
+SOURCES=index.html style.css
+
+index.html: index.org
+	emacs --batch -l org2html.el index.org
+
+clean: index.html
+
+.PHONY: .cache
+.cache:
+	@if test -d .cache ; then \
+	  cd .cache && cvs update ; \
+	else \
+          mkdir .cache && \
+	  cvs -z3 -d $(CVSREPO) co -d .cache xenv; \
+	fi
+
+update: .cache index.html
+	rsync -az $(SOURCES) .cache
+	cd .cache && cvs commit -m 'Update'
diff --git a/index.org b/index.org
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+++ b/index.org
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+* Overview
+
+*Xenv* is a text preprocessor that expands references to environment
+variables in the input text to their actual values.  Environment 
+variables are referenced using POSIX-compatible shell syntax.
+Text is read from the standard input and expanded text goes to the
+standard output.
+
+* Rationale
+
+It became a de-facto practice to configure docker containers using 
+environment variables.  The method is obvious when configuration
+is consumed by some programming language (*php*, *python* or the
+like).  However, sometimes the need arises to expand environment
+variables in configuration files of the utilities that provide no
+mechanism for this (such as *mysqld* or *ldap*, for instance).
+
+I often use [[http://puszcza.gnu.org.ua/software/pies/][GNU pies]] as entrypoint for images I produce.  It uses
+[[https://www.gnu.org/software/m4][m4]] for preprocessing its configuration.  Several mechanisms have
+been proposed for expanding environment variables in it: implementing
+special
+[[http://puszcza.gnu.org.ua/software/pies/manual/Docker-Entrypoint.html][macros]] or a [[http://git.gnu.org.ua/cgit/gsc/m4env.git/][wrapper program]].  However, the shortcomings of both 
+became apparent and the need of something more convenient motivated 
+the inception of this utility.
+
+* Variable references
+
+The input text can reference the environment variables using the
+following constructs:
+
+- $ _variable_
+
+  The value of _variable_ is substituted.
+
+- ${ _variable_ }
+
+  The value of _variable_ is substituted.
+
+- ${ _variable_ :- _word_ }
+
+  If _variable_ is unset or null, the expansion of _word_ is substituted.
+  Otherwise, the value of _variable_ is substituted.
+
+- ${ _variable_ := _word_ }
+
+  If _variable_ is unset or null, the expansion of _word_ is
+  assigned to _variable_.  The value of _variable_ is then substituted.
+
+- ${ _variable_ :? _word_ }
+
+  If _variable_ is null or unset, the expansion of _word_ (or a
+  message to that effect if word is not present) is output to standard error.
+  Otherwise, the value of _variable_ is substituted.
+
+- ${ _variable_ :+ _word_ }
+
+  If _variable_ is null or unset, nothing is substituted, otherwise the
+  expansion of _word_ is substituted.
+
+- ${ _variable_ :| _word1_ | _word2_ }
+
+  Unless _variable_ is null or unset, substitues the expansion of
+  _word1_, otherwise the expansion of _word2_.
+
+In the constructs above the colon can be omitted, resulting in a test
+only for a variable that is unset.
+
+The _indirection operator_ *$* can be changed to another symbol using 
+the command line option *-S*.
+
+* Documentation
+
+The documentaion for *xenv* is [[http://man.gnu.org.ua/manpage/?1+xenv][available online]].
+
+* Downloads
+
+Download the [[https://download.gnu.org.ua/release/xenv/xenv-1.1.tar.gz][latest version]] of *xenv*.
+
+The tarball is signed using the author's GPG key.  To verify it,
+import the author's key using the following command:
+
+#+BEGIN_SRC shell-script
+gpg --keyserver keys.gnupg.net --recv-keys 3602B07F55D0C732
+#+END_SRC
+
+Then, download the [[https://download.gnu.org.ua/release/xenv/xenv-1.1.tar.gz.sig][signature]] file and run
+
+#+BEGIN_SRC shell-script
+gpg --verify xenv-1.1.tar.gz
+#+END_SRC
+
+Checksums for this tarball are [[https://puszcza.gnu.org.ua/forum/forum.php?forum_id=1270][listed here]].
+
+This and other versions of the utility can be downloaded from
+https://download.gnu.org.ua/release/xenv (the *ftp* protocol
+is also supported).
+
+** Other references:
+
+- [[https://puszcza.gnu.org.ua/projects/xenv][Project development page]]
+
+- [[http://git.gnu.org.ua/cgit/xenv.git][Git repository]]
+
+* Bug reports
+
+If you think you found a bug in *xenv* or in its documentation, please 
+send a mail to [[mailto:gray@gnu.org][Sergey Poznyakoff]] or use the web [[https://puszcza.gnu.org.ua/bugs/?group=xenv][bug tracker]].
+
+* Copyright
+
+Copyright (C) 2021 Sergey Poznyakoff
+
+Permission is granted to anyone to make or distribute verbatim copies
+of this document as received, in any medium, provided that the
+copyright notice and this permission notice are preserved,
+thus giving the recipient permission to redistribute in turn.
+
+Permission is granted to distribute modified versions
+of this document, or of portions of it,
+under the above conditions, provided also that they
+carry prominent notices stating who last changed them.
+
+* Document settings :noexport:
+
+Please ignore this section. It supplies the variables necessary for
+proper rendering of this document.
+
+:PROPERTIES:
+:VISIBILITY: folded
+:END:
+
+#+TITLE: xenv
+#+STARTUP: showall
+#+EXCLUDE_TAGS: noexport
+#+HTML_HEAD: <link rel="stylesheet" type="text/css" href="style.css" />
+#+OPTIONS: ^:nil
+
+# Local Variables:
+# mode: org
+# paragraph-separate: "[ 	^L]*$"
+# version-control: never
+# End:
diff --git a/org2html.el b/org2html.el
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--- /dev/null
+++ b/org2html.el
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+(let ((bufname (car command-line-args-left))
+      (target (car (cdr command-line-args-left))))
+  (set-buffer (find-file bufname))
+  (let ((name (org-html-export-to-html)))
+    (if target
+        (rename-file name target t))
+    (kill-buffer (current-buffer))))
diff --git a/style.css b/style.css
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--- /dev/null
+++ b/style.css
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+/* Basic settings */
+body {
+	margin-left: auto;
+	margin-right: auto;
+	max-width: 80em;
+	background-color: silver;
+        padding: 4px;
+}
+html {}
+div {
+    background-color: white;
+}
+
+div#content {
+      margin-top: 2em;
+      margin-left: 5%;
+      margin-right: 5%;
+      padding: 1em;
+      border: 1px solid black;
+}
+
+div#postamble {
+    margin-bottom: 2em;
+    margin-left: 5%;
+    margin-right: 5%;
+    border: 1px solid black;
+    font-size: 80%;
+    padding: 4px;
+}
+
+.title  { text-align: center; }
+.todo   { color: red; }
+.done   { color: green; }
+.tag    { background-color: #add8e6; font-weight:normal }
+.target { }
+.timestamp { color: #bebebe; }
+.timestamp-kwd { color: #5f9ea0; }
+.right  {margin-left:auto; margin-right:0px;  text-align:right;}
+.left   {margin-left:0px;  margin-right:auto; text-align:left;}
+.center {margin-left:auto; margin-right:auto; text-align:center;}
+p.verse { margin-left: 3% }
+pre {
+    border: 1pt solid #AEBDCC;
+    background-color: #F3F5F7;
+    padding: 5pt;
+    font-family: courier, monospace;
+    font-size: 90%;
+    overflow:auto;
+}
+table { border-collapse: collapse; }
+td, th { vertical-align: top;  }
+th.right  { text-align:center;  }
+th.left   { text-align:center;   }
+th.center { text-align:center; }
+td.right  { text-align:right;  }
+td.left   { text-align:left;   }
+td.center { text-align:center; }
+dt { font-weight: bold; }
+div.figure { padding: 0.5em; }
+div.figure p { text-align: center; }
+div.inlinetask {
+    padding:10px;
+    border:2px solid gray;
+    margin:10px;
+    background: #ffffcc;
+}
+textarea { overflow-x: auto; }
+.linenr { font-size:smaller }
+.code-highlighted {
+    background-color:#ffff00;
+}
+.org-info-js_info-navigation {
+    border-style:none;
+}
+#org-info-js_console-label {
+    font-size:10px;
+    font-weight:bold;
+    white-space:nowrap;
+}
+.org-info-js_search-highlight {
+    background-color:#ffff00;
+    color:#000000;
+    font-weight:bold;
+}
+