[llvm] [llvm-strings] Add --encoding={s,S,u} option (PR #221794)

[Harald van Dijk via llvm-commits]

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@@ -40,8 +40,15 @@ Silently ignored. Present for GNU {program}`strings` compatibility.
 :::
 
 :::{option} --bytes=<length>, -n
-Set the minimum number of printable ASCII characters required for a sequence of
-bytes to be considered a string. The default value is 4.
+Set the minimum number of printable characters required for a sequence to be
+considered a string. The default value is 4.
+:::
+
+:::{option} --encoding=<encoding>, -e
+Specifies the encoding of the input file. Valid arguments are:
+- s (ASCII characters)
+- S (characters in the system's or user's selected character set)
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hvdijk wrote:

In what ways the default character set can be changed depends on the OS. On older Windows systems (no longer supported by LLVM), it couldn't be changed at all. On current Windows systems, it can be changed, but as far as I know it's a system setting, different users on the same system cannot use different character sets. On Unix-like systems (including macOS), it can be changed per process by setting appropriate environment variables. Maybe "characters in the default character set" would work?

https://github.com/llvm/llvm-project/pull/221794