"How to embed perl in your C program"
- a good starting point on the Perl C API
"perlguts -- Introduction to the Perl API"
- more detail
- reference documentation
cbits/glue.c largely contain wrappers around Perl C API
functions (documented in https://perldoc.perl.org/perlapi), adding a
hsperl_ prefix to them. This is necessary because the "functions"
are often actually macros, and macro trickery is used to make them
operate on an implicit Perl interpreter instance.
cbits/glue.h, unsurprisingly, contains prototypes for the functions
in cbits/glue.c.
cbits/perlxsi.h contains an xs_init() function, required for the
Perl interpreter to be initialized. It's generated by running
perl -MExtUtils::Embed -e xsinit -- -o cbits/perlxsi.h
It's checked into version control, despite being a generated file,
because it seems to be standard boilerplate that doesn't change from
one Perl installation to another. (The standard name for the file
is perlxsi.c, but we use it as a header.)
You'll want to run the following command in vim:
: let g:intero_ghci_options='-fobject-code -O0'
else Intero won't start properly.