Allow one to set a custom progress callback (#2609)

ming030890

2025-08-05 b3fb4c0acd5f52a313f024b6f69b8f025c6eddfe

1
2
3
4
5
6
7
8
9
I    1
II    2
III    3
IV    4
V    5
VI    6
VII    7
VIII    8
IX    9