Expand description
Program startup and shutdown.
To use origin’s program startup, define a function named origin_main like
this:
/// This function is called by Origin.
///
/// SAFETY: `argc`, `argv`, and `envp` describe incoming program
/// command-line arguments and environment variables.
#[no_mangle]
unsafe fn origin_main(argc: usize, argv: *mut *mut u8, envp: *mut *mut u8) -> i32 {
todo!("Run the program and return the program exit status.")
}Origin will call this function after starting up the program and running
the constructors. argc is the number of command-line arguments with a
value of at most c_int::MAX, and argv is a pointer to a NULL-terminated
array of pointers to NUL-terminated C strings. argc and argv describe
the command-line arguments. envp is a pointer to a NULL-terminated array
of pointers to NUL-terminated C strings containing a key followed by b'='
followed by a value. It describes the environment variables. The function
should return a value for the program exit status.
This is a low-level and somewhat C-flavored interface, which is in tension with origin’s goal of providing Rust-idiomatic interfaces, however it does mean that origin can avoid doing any work that users might not need.