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| author | Laurent Bercot <ska-skaware@skarnet.org> | 2014-09-18 20:03:23 +0000 |
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| committer | Laurent Bercot <ska-skaware@skarnet.org> | 2014-09-18 20:03:23 +0000 |
| commit | f316a2ed52195135a35e32d7096e876357c48c69 (patch) | |
| tree | 5f4486b9a5a213a69e66ef574d6bc643a207981c /doc/ifte.html | |
| download | execline-f316a2ed52195135a35e32d7096e876357c48c69.tar.xz | |
initial commit: rc for execline-2.0.0.0
Diffstat (limited to 'doc/ifte.html')
| -rw-r--r-- | doc/ifte.html | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/doc/ifte.html b/doc/ifte.html new file mode 100644 index 0000000..40b0ec9 --- /dev/null +++ b/doc/ifte.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 ifte command</title> + <meta name="Description" content="execline: the ifte command" /> + <meta name="Keywords" content="execline command ifte" /> + <!-- <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>ifte</tt> program </h1> + +<p> +<tt>ifte</tt> performs a conditional alternative. +</p> + +<h2> Interface </h2> + +<p> + In an <a href="execlineb.html">execlineb</a> script: +</p> + +<pre> + ifte [ -X ] [ -n ] { <em>progthen...</em> } { <em>progelse...</em> } <em>progif...</em> +</pre> + +<ul> + <li> <tt>ifte</tt> reads <em>progthen...</em> and <em>progelse...</em> in two +consecutive <a href="el_semicolon.html">blocks</a>. </li> + <li> <tt>ifte</tt> runs <em>progif...</em> as a child process +and waits for it to complete. </li> + <li> If <em>progif...</em> crashes (i.e. is killed by a signal), <tt>ifte</tt> +exits 1 with an error message. </li> + <li> If <em>progif...</em> exits zero, <tt>ifte</tt> execs into +<em>progthen...</em>, else it execs into <em>progelse...</em>. </li> +</ul> + +<h2> Options </h2> + +<ul> + <li> <tt>-X</tt> : do not exit if <em>progif</em> crashes; instead, +proceed as if the test had returned false. </li> + <li> <tt>-n</tt> : negate the test. <em>progthen...</em> will be run +iff <em>progif...</em> exits nonzero. </li> +</ul> + +<h2> Notes </h2> + +<p> + <tt>ifte</tt> is a simpler version of <a href="ifthenelse.html">ifthenelse</a>. +It performs <em>only</em> conditional execution, not instruction sequence. +</p> + +<p> +"<tt>ifthenelse { progif } { progthen } { progelse } remainder</tt>" is the +equivalent of "<tt>foreground { ifte { progthen } { progelse } progif } remainder</tt>". +</p> + +</body> +</html> |