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| -rw-r--r-- | doc/dieshdiedie.html | 19 |
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diff --git a/doc/dieshdiedie.html b/doc/dieshdiedie.html index 584b781..3bac160 100644 --- a/doc/dieshdiedie.html +++ b/doc/dieshdiedie.html @@ -33,15 +33,16 @@ on the subject</a>, section 5.) of the shell is parsing: the parser and the runner are intimately interleaved and cannot be clearly separated, thanks to the <a href="http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html">specification</a>. -Even worse, the -shell sometimes has to perform <em>double parsing</em>, for instance -after parameter expansion. This can lead to atrocities like -<pre> -zork="foo ; echo bar" -touch $zork -</pre> not doing what you would like them to do, even in that simple -case. (<a href="http://www.zsh.org/">zsh</a> has a sane behaviour by -default, at the expense of explicitly breaking the spec.) +The shell performs several kinds of expansions, automatic filename +globbing, and automatic word splitting, in an unintuitive order, +requiring users to memorize numerous arbitrary quoting rules in +order to achieve what they want. Pages +<a href="http://www.google.com/search?q=shell+script+pitfalls">abound</a> +where common mistakes are listed, more often than not leading to +security holes. Did you know that <tt>"$@"</tt> is a special case +of double quoting, because it will split the arguments into +several words, whereas every other use of double quotes in a shell is +meant to <em>prevent</em> splitting? </p> <p> |