coreutils: Charset selection in ptx
7.5.2 Charset selection
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As it is set up now, ‘ptx’ assumes that the input file is coded using
8-bit characters, and it may not work well in multibyte locales. In a
single-byte locale, the default regular expression for a keyword allows
foreign or diacriticized letters. Keyword sorting, however, is still
crude; it obeys the underlying character set ordering quite blindly.
The output of ‘ptx’ assumes the locale’s character encoding. For
example, with ‘ptx’’s ‘-T’ option, if the locale uses the Latin-1
encoding you may need a LaTeX directive like
‘\usepackage[latin1]{inputenc}’ to render non-ASCII characters
correctly.
‘-f’
‘--ignore-case’
Fold lower case letters to upper case for sorting.