From 1fe45d48b1a898df751473638b28c3553ca6d169 Mon Sep 17 00:00:00 2001
From: koalaman <vidar@vidarholen.net>
Date: Sat, 31 Oct 2015 17:30:54 -0700
Subject: [PATCH] Created SC2172 (markdown)

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+## Trapping signals by number is not well defined. Prefer signal names.
+
+### Problematic code:
+
+```sh
+trap myfunc 28
+```
+
+### Correct code:
+
+```sh
+trap myfunc WINCH
+```
+### Rationale:
+
+Signal numbers can vary between platforms. Prefer signal names, which are fixed.
+
+Signal numbers 1, 2, 3, 6, 9, 14 and 15 are specified as parts of the optional POSIX XSI and ShellCheck will not warn about these. 
+
+### Exceptions:
+
+None.
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