Function kdbplus::api::native::setm

pub unsafe extern "C" fn setm(lock: I) -> I

Set whether interning symbols uses a lock: lock is either 0 or 1. Returns the previously set value.

Example

#[macro_use]
extern crate kdbplus;
use kdbplus::api::*;
use kdbplus::api::native::*;
 
#[no_mangle]
pub extern "C" fn parallel_sym_change(list: K) -> K{
  unsafe{
    // `K` cannot have `Send` because it is a pointer but `k0` does.
    let mut inner=*list;
    // Lock symbol before creating an internal symbol on another thread.
    setm(1);
    let task=std::thread::spawn(move || {
       inner.as_mut_slice::<S>()[0]=ss(str_to_S!("replaced"));
       inner
    });
    list.as_mut_slice::<S>()[1]=ss(str_to_S!("symbolbol"));
    match task.join(){
      Err(_) => {
        // Unlock.
        setm(0);
        krr(null_terminated_str_to_const_S("oh no"))
      },
      Ok(l) => {
        // Unlock.
        setm(0);
        (*list)=l;
        // Increment reference count for copy.
        r1(list)
      }
    }
  }
}

q)alms_with_left_hand: `libc_api_examples 2: (`parallel_sym_change; 2);
q)alms_with_left_hand[`a`b];
`replaced`symbolbol