int  subscript;

For the current barcode type (i.e. itype in a call to BarInfo), this variable returns the number of supplementary characters required for a valid code, or 0 for coding schemes that do not require a supplement.

Note that this number is does not include the number of characters in the primary code; thus EAN 13 with a 5 character supplement returns 5 in this variable.

 

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int textgap;