:sig
int file_open_locked(String file_name, int open_flags, int lock_type = LOCK_SH, int create_mode = 0644, f64 wait_timeout_seconds = 3.0, String purpose = "")

:params
file_name : path to open
open_flags : host open(2) flags
lock_type : `LOCK_SH` or `LOCK_EX`
create_mode : mode used when creating
return value : opaque locked file handle, or -1

:see
>sys
>file_close_locked
>file_get_contents_locked_fd
>file_put_contents_locked_fd

:content
Opens and locks a file on the host. In wasm units the returned integer is an opaque worker-owned handle that is valid only for the current request.