Function xmlShellWrite 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn xmlShellWrite(
    ctxt: *mut _xmlShellCtxt,
    filename: *mut c_char,
    node: *mut _xmlNode,
    _node2: *mut _xmlNode,
) -> c_int

int xmlShellWrite(xmlShellCtxtPtr ctxt, char *filename, xmlNodePtr node, xmlNodePtr node2) — the shell “write” command: write the subtree under node to filename.