/usr/share/man/man3/gcpExit.3.gz is in libggigcp1-dev 1.0.2+dfsg1-2.1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man3/gcpInit.3.gz
/usr/share/man/man3/gcpInit.3.gz