Mirror of forum.nim-lang.org

8626 :: what does bycopy mean

• JPLRouge (orginal) [2021-11-14T19:25:48+01:00] view original

  hello

  
  type
    msg_buf* {.bycopy.} = object
      mtype*: clong
      mtext*: array[MSGTXTLEN, char]
  var Q_msg*: msg_buf
  Run

  I have a header H

  with

  struct msg_buf {

  long mtype; char mtext [MSGTXTLEN];

  } Q_msg;

  will bycopy share the structure

  thank you

---

• leorize (orginal) [2021-11-15T00:28:40+01:00] view original

  {.bycopy.} means that the structure will always be passed via a copy in Nim, which is C semantics. As such you will see it on structures used to interoperate with C code.

---