perlxstut(1) on OpenBSD
The text 8a235431d9ea, as OpenBSD 7.2, OpenBSD 7.1, OpenBSD 7.0, OpenBSD 6.9 shipped it.
Tutorial for writing XSUBs
The text 8a235431d9ea, as OpenBSD 7.2, OpenBSD 7.1, OpenBSD 7.0, OpenBSD 6.9 shipped it.
Tutorial for writing XSUBs