fix posix.mq_receive compilation with cpp backend (#20710)

* fix posix.mq_receive compilation with cpp backend

* only enable runnableExample on posix

* linux, not posix

* simplify example

* add test

* mqueue.h does not exist on MacOS

* place test case in own block

* drop runnableExamples

1 files changed, 41 insertions, 15 deletions

diff --git a/lib/posix/posix.nim b/lib/posix/posix.nim
index 317cc8735..ddf00cbb7 100644
--- a/lib/posix/posix.nim
+++ b/lib/posix/posix.nim
@@ -249,26 +249,52 @@ proc setlocale*(a1: cint, a2: cstring): cstring {.
 proc strfmon*(a1: cstring, a2: int, a3: cstring): int {.varargs,
    importc, header: "<monetary.h>".}
 
-when not defined(nintendoswitch):
-  proc mq_close*(a1: Mqd): cint {.importc, header: "<mqueue.h>".}
-  proc mq_getattr*(a1: Mqd, a2: ptr MqAttr): cint {.
-    importc, header: "<mqueue.h>".}
-  proc mq_notify*(a1: Mqd, a2: ptr SigEvent): cint {.
+when not (defined(nintendoswitch) or defined(macos) or defined(macosx)):
+  proc mq_notify*(mqdes: Mqd, event: ptr SigEvent): cint {.
     importc, header: "<mqueue.h>".}
-  proc mq_open*(a1: cstring, a2: cint): Mqd {.
+
+  proc mq_open*(name: cstring, flags: cint): Mqd {.
     varargs, importc, header: "<mqueue.h>".}
-  proc mq_receive*(a1: Mqd, a2: cstring, a3: int, a4: var int): int {.
-    importc, header: "<mqueue.h>".}
-  proc mq_send*(a1: Mqd, a2: cstring, a3: int, a4: int): cint {.
+
+  proc mq_close*(mqdes: Mqd): cint {.importc, header: "<mqueue.h>".}
+
+  proc mq_receive*(
+    mqdes: Mqd,
+    buffer: cstring,
+    length: csize_t,
+    priority: var cuint
+  ): int {.importc, header: "<mqueue.h>".}
+
+  proc mq_timedreceive*(
+    mqdes: Mqd,
+    buffer: cstring,
+    length: csize_t,
+    priority: cuint,
+    timeout: ptr Timespec
+  ): int {.importc, header: "<mqueue.h>".}
+
+  proc mq_send*(
+    mqdes: Mqd,
+    buffer: cstring,
+    length: csize_t,
+    priority: cuint
+  ): cint {.importc, header: "<mqueue.h>".}
+
+  proc mq_timedsend*(
+    mqdes: Mqd,
+    buffer: cstring,
+    length: csize_t,
+    priority: cuint,
+    timeout: ptr Timespec
+  ): cint {.importc, header: "<mqueue.h>".}
+
+  proc mq_getattr*(mqdes: Mqd, attribute: ptr MqAttr): cint {.
     importc, header: "<mqueue.h>".}
-  proc mq_setattr*(a1: Mqd, a2, a3: ptr MqAttr): cint {.
+
+  proc mq_setattr*(mqdes: Mqd, newAttribute, oldAttribute: ptr MqAttr): cint {.
     importc, header: "<mqueue.h>".}
 
-  proc mq_timedreceive*(a1: Mqd, a2: cstring, a3: int, a4: int,
-                        a5: ptr Timespec): int {.importc, header: "<mqueue.h>".}
-  proc mq_timedsend*(a1: Mqd, a2: cstring, a3: int, a4: int,
-                     a5: ptr Timespec): cint {.importc, header: "<mqueue.h>".}
-  proc mq_unlink*(a1: cstring): cint {.importc, header: "<mqueue.h>".}
+  proc mq_unlink*(mqdes: cstring): cint {.importc, header: "<mqueue.h>".}
 
 
 proc getpwnam*(a1: cstring): ptr Passwd {.importc, header: "<pwd.h>".}