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README.md

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+# SRFI 238 - portable string-based implementation
+
+This is an implementation SRFI 238 based around the following C
+interface.
+
+```
+char *codeset_list(void);
+char *codeset_numbers(const char *codeset);
+char *codeset_symbols(const char *codeset);
+char *codeset_messages(const char *codeset);
+```
+
+Each function returns a newline-delimited C string.
+
+The idea is to make the interface so simple that it can be wrapped
+easily using the FFI of any Scheme implementation that has one.
+(Non-Scheme languages like Common Lisp or ML could make use of the
+same C code.)
+
+The downside is that memory usage is not optimal. All strings are
+retrieved from C at once, and half of the string handling is done in
+Scheme.