diff options
| author | Laurent Bercot <ska-skaware@skarnet.org> | 2014-09-18 20:03:23 +0000 |
|---|---|---|
| committer | Laurent Bercot <ska-skaware@skarnet.org> | 2014-09-18 20:03:23 +0000 |
| commit | f316a2ed52195135a35e32d7096e876357c48c69 (patch) | |
| tree | 5f4486b9a5a213a69e66ef574d6bc643a207981c /doc/pipeline.html | |
| download | execline-f316a2ed52195135a35e32d7096e876357c48c69.tar.xz | |
initial commit: rc for execline-2.0.0.0
Diffstat (limited to 'doc/pipeline.html')
| -rw-r--r-- | doc/pipeline.html | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/doc/pipeline.html b/doc/pipeline.html new file mode 100644 index 0000000..4f6677f --- /dev/null +++ b/doc/pipeline.html @@ -0,0 +1,67 @@ +<html> + <head> + <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> + <meta http-equiv="Content-Language" content="en" /> + <title>execline: the pipeline command</title> + <meta name="Description" content="execline: the pipeline command" /> + <meta name="Keywords" content="execline command pipeline" /> + <!-- <link rel="stylesheet" type="text/css" href="http://skarnet.org/default.css" /> --> + </head> +<body> + +<p> +<a href="index.html">execline</a><br /> +<a href="http://skarnet.org/software/">Software</a><br /> +<a href="http://skarnet.org/">skarnet.org</a> +</p> + +<h1> The <tt>pipeline</tt> program </h1> + +<p> +<tt>pipeline</tt> runs two commands with a pipe between them. +</p> + +<h2> Interface </h2> + +<p> + In an <a href="execlineb.html">execlineb</a> script: +</p> + +<pre> + pipeline [ -d ] [ -r | -w ] { <em>prog1...</em> } <em>prog2...</em> +</pre> + +<ul> + <li> <tt>pipeline</tt> reads <em>prog1...</em> in a +<a href="el_semicolon.html">block</a> and unquotes it. </li> + <li> It runs <em>prog1...</em> as a child process and execs into +<em>prog2...</em>, with a pipe between <em>prog1</em>'s stdout and +<em>prog2</em>'s stdin. </li> + <li> <em>prog1</em>'s pid is available in <em>prog2</em> as the ! +environment variable. </li> +</ul> + +<h2> Options </h2> + +<ul> + <li> <tt>-d</tt> : run <em>prog1...</em> +as a grandchild of <tt>pipeline</tt>. This is meant to prevent a zombie +from hanging around if <em>prog2...</em> fails to wait for its children.</li> + <li> <tt>-r</tt> : make <em>prog1...</em> the writer and +<em>prog2...</em> the reader. This is the default. </li> + <li> <tt>-w</tt> : make <em>prog1...</em> the reader and +<em>prog2...</em> the writer. </li> +</ul> + +<h2> Notes </h2> + +<ul> + <li> You can easily create a chain of pipes: <tt>pipeline a "" pipeline b "" c</tt> +is roughly equivalent to +<tt>sh -c 'exec a | b | c'</tt>, except that shells usually run <tt>c</tt> +as a child process like <tt>a</tt> and <tt>b</tt>, and <tt>exec</tt> has no +effect. </li> +</ul> + +</body> +</html> |