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<p>
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<h1> The <tt>forx</tt> program </h1>
<p>
<tt>forx</tt> runs a loop.
</p>
<h2> Interface </h2>
<p>
In an <a href="execlineb.html">execlineb</a> script:
</p>
<pre>
forx [ -E | -e ] [ -p | -P <em>maxpar</em> ] [ -o <em>okcodes</em> | -x <em>breakcodes</em> ] <em>variable</em> { <em>args...</em> } <em>loop...</em>
</pre>
<ul>
<li> <tt>forx</tt> reads a
<a href="el_semicolon.html">block</a> and unquotes it.
That block contains a list of <em>args</em>. </li>
<li> For each argument <em>x</em> in <em>args...</em>,
<tt>forx</tt> runs <em>loop</em> as a child process, with
<em>variable</em>=<em>x</em> added to its environment. </li>
<li> <tt>forx</tt> then exits 0. </li>
</ul>
<h2> Options </h2>
<ul>
<li> <tt>-o</tt> <em>okcodes</em> : <em>okcodes</em> must
be a comma-separated list of exit codes. If
<em>loop</em> exits with one of the codes in <em>okcodes</em>,
forx will run the following instances of the loop, but if the exit code is
not listed in <em>okcodes</em>, forx will exit immediately with an
<a href="exitcodes.html">approximation</a> of the same exit code. </li>
<li> <tt>-x</tt> <em>breakcodes</em> : like the previous
option, but with inverted meaning - the listed exit codes are codes
that will make forx break the loop and exit, and the unlisted exit
codes will make it keep looping. </li>
<li> <tt>-p</tt> : run in parallel. Do not wait for an instance of
<em>loop...</em> to exit before spawning the next one. <tt>forx</tt>
will still wait for all instances of <em>loop</em> to terminate before
exiting 0. If the <tt>-o</tt> option has been given, <tt>forx</tt>
will exit 0 if all of the exit codes are in the values listed in the <em>okcodes</em>
list, else it will exit 1. If the <tt>-x</tt> option has been given,
<tt>forx</tt> will exit 0 if none of the exit codes are in the values
listed in the <em>breakcodes</em> list, else it will exit 1. </li>
<li> <tt>-e</tt> : no autoimport. This is the default. </li>
<li> <tt>-E</tt> : autoimport. Instead of spawning
<em>loop...</em>, spawn <tt>importas -uSi <em>variable</em>
<em>loop...</em></tt>. This substitutes <em>variable</em> into the command
line instead of putting it into the environment. </li>
<li> <tt>-P</tt> <em>maxpar</em> : similar to <tt>-p</tt>, but run
up to <em>maxpar</em> instances in parallel, i.e. never have more than <em>maxpar</em>
children at the same time. Minimum is 1. </li>
</ul>
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