In PRO/5 Rev. 3.10 and higher, the LCHECKIN() verb checks in a license
(FLEXlm/FLEXnet Application Licensing)
that was checked out by LCHECKOUT(). The integer handle should be the
handle that was returned by a successful LCHECKOUT().
See also LCHECKOUT() Function - Check Out License and LINFO() Function - License Information.