Patch-Source: https://github.com/thestk/rtmidi/pull/278
From cfe34c02112c256235b62b45895fc2c401fd874d Mon Sep 17 00:00:00 2001
From: Niclas Rosenvik <youremailsarecrap@gmail.com>
Date: Sun, 19 Dec 2021 13:56:27 +0100
Subject: [PATCH] Use posix sched_yield instead of pthread_yield

Use posix sched_yield instead of pthread_yield.
pthread_yield is linux specific sched_yield is
a standard posix function. pthread_yield on linux
is implemented using sched_yield.
This makes the jack plugin work on other
platforms than linux.
---
 RtMidi.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/RtMidi.cpp b/RtMidi.cpp
index 6a1c89e..88b55e1 100644
--- a/RtMidi.cpp
+++ b/RtMidi.cpp
@@ -3092,6 +3092,7 @@ void MidiOutWinMM :: sendMessage( const unsigned char *message, size_t size )
 #include <jack/midiport.h>
 #include <jack/ringbuffer.h>
 #include <pthread.h>
+#include <sched.h>
 #ifdef HAVE_SEMAPHORE
   #include <semaphore.h>
 #endif
@@ -3608,7 +3609,7 @@ void MidiOutJack :: sendMessage( const unsigned char *message, size_t size )
       return;
 
   while ( jack_ringbuffer_write_space(data->buff) < sizeof(nBytes) + size )
-      pthread_yield();
+      sched_yield();
 
   // Write full message to buffer
   jack_ringbuffer_write( data->buff, ( char * ) &nBytes, sizeof( nBytes ) );