Paul Thompson wrote:
> What sort of documentation is available for \pdfstrcmp?  I confess that I have 
> never heard of this toolset.

pdfTeX manual says:

\pdfstrcmp <general text> <general text> (expandable)
This command compares two strings and expands to 0 if the strings are
equal, to -1 if the first string ranks before the second, and to 1
otherwise. The primitive was introduced in pdfTEX 1.30.0.

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