Revert backtick to a non-wrapper; add -I to backtick and withstdinas

1 files changed, 17 insertions, 10 deletions

diff --git a/doc/backtick.html b/doc/backtick.html
index 6aa2f01..694a29d 100644
--- a/doc/backtick.html
+++ b/doc/backtick.html
@@ -46,20 +46,27 @@ output as a value. </li>
 <h2> Options </h2>
 
 <ul>
- <li> <tt>-i</tt>&nbsp;: insist. If <em>prog1</em> crashes or exits non-zero,
-<tt>backtick</tt> exits with an
-<a href="exitcodes.html">approximation</a> of the same exit code. </li>
- <li> <tt>-D&nbsp;<em>default</em></tt>&nbsp;: default value. If
-<em>prog1</em> crashes or exits non-zero, <em>default</em> is used as
-<em>variable</em>'s value. If neither the <tt>-i</tt> nor the <tt>-D</tt>
-option have been given, <tt>backtick</tt> execs into
-<em>prog2...</em> no matter what <em>prog1</em> does, with the null word as
-<em>variable</em>'s value if <em>prog1</em> didn't write anything before
-dying. </li>
  <li> <tt>-n</tt>&nbsp;: chomp an ending newline off <em>prog1...</em>'s
 output. </li>
 </ul>
 
+<p>
+ The other options tell backtick what to do if <em>prog1...</em>'s output
+is not suitable as the contents of an environment variable, i.e. it
+contains a null character:
+</p>
+
+<ul>
+ <li> <tt>-i</tt>&nbsp;: backtick exits 1. </li>
+ <li> <tt>-I</tt>&nbsp;: <em>variable</em> is <strong>removed</strong> from
+the environment, and execution proceeds. </li>
+ <li> <tt>-D&nbsp;<em>default</em></tt>&nbsp;: the value of <em>variable</em>
+is set to <em>default</em>, and execution proceeds. </li>
+ <li> neither of those options: the value of <em>variable</em> is set to whatever
+the start of <em>prog1...</em>'s output is, up to the first null character;
+then execution proceeds. </li>
+</ul>
+
 <h2> Notes </h2>
 
 <ul>