Return a file offset if there was an error parsing a leader.
Return a file offset if there was an error parsing a leader.

ubtue/ub_tools,ubtue/ub_tools,ubtue/ub_tools,ubtue/ub_tools,ubtue/ub_tools,ubtue/ub_tools,ubtue/ub_tools,ubtue/ub_tools