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--- posix_shell_getpots [2019/09/25 18:03] – created rpjday
+++ posix_shell_getpots [2019/09/30 12:16] (current) – [Starting points] rpjday
@@ Line 2: / Line 2: @@
 An attempt at summarizing the //right// way to use POSIX-compliant ''getopts''.
+A couple links:
+  * [[https://pubs.opengroup.org/onlinepubs/9699919799/utilities/getopts.html|https://pubs.opengroup.org/onlinepubs/9699919799/utilities/getopts.html]]
+    * [[https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap12.html#tag_12_02|https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap12.html#tag_12_02]]
+  * [[https://sookocheff.com/post/bash/parsing-bash-script-arguments-with-shopts/|https://sookocheff.com/post/bash/parsing-bash-script-arguments-with-shopts/]]
+===== Starting points =====
+First, there has been much blood spilled discussing how to support //optional// arguments using ''getopts'' -- the correct solution is to not do that, as explained in Guideline 7 [[https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap12.html#tag_12_02|here]]. So we won't.
+And, second, if the //optstring// handed to getopts starts with a colon, then getopts uses what is called "silent error reporting"; this appears to be the recommended approach, so we'll stick with that. In short, don't do this:
+<code>
+while getopts ab:c: opt ; do
+</code>
+Do this (note the leading colon):
+<code>
+while getopts :ab:c: opt ; do
+</code>
+Explanation below.
+===== Fleshed out example =====
+<code>
+... coming soon ...
+</code>