Man page - fccharsetsubtractcount(3)
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Manual
FcCharSetSubtractCount
NAMESYNOPSIS
DESCRIPTION
NAME
FcCharSetSubtractCount - Subtract and count charsets
SYNOPSIS
#include <fontconfig/fontconfig.h>
FcChar32 FcCharSetSubtractCount (const FcCharSet * a , const FcCharSet * b );
DESCRIPTION
Returns the number of chars that are in a but not in b .