Parse an ASCII decimal or hexadecimal integer into a BIGNUM.
A leading '-' sets the negative flag. Trailing non-digit characters are ignored after a successful parse of a number prefix.
1 on success, or 0 on parse error.
| Name | Description |
|---|---|
| a | Location of the BIGNUM pointer; allocated if *a is NULL. |
| str | Decimal digits, or a hex string with a leading "0x" / "0X". |