diff --git a/block/file-posix.c b/block/file-posix.c
index c000a61..39a3d6d 100644
--- a/block/file-posix.c
+++ b/block/file-posix.c
@@ -3320,17 +3320,23 @@
 #if defined(__APPLE__) && defined(__MACH__)
 static kern_return_t GetBSDPath(io_iterator_t mediaIterator, char *bsdPath,
                                 CFIndex maxPathSize, int flags);
+
+#if !defined(MAC_OS_VERSION_12_0) \
+    || (MAC_OS_X_VERSION_MIN_REQUIRED < MAC_OS_VERSION_12_0)
+#define IOMainPort IOMasterPort
+#endif
+
 static char *FindEjectableOpticalMedia(io_iterator_t *mediaIterator)
 {
     kern_return_t kernResult = KERN_FAILURE;
-    mach_port_t     masterPort;
+    mach_port_t mainPort;
     CFMutableDictionaryRef  classesToMatch;
     const char *matching_array[] = {kIODVDMediaClass, kIOCDMediaClass};
     char *mediaType = NULL;
 
-    kernResult = IOMasterPort( MACH_PORT_NULL, &masterPort );
+    kernResult = IOMainPort(MACH_PORT_NULL, &mainPort);
     if ( KERN_SUCCESS != kernResult ) {
-        printf( "IOMasterPort returned %d\n", kernResult );
+        printf("IOMainPort returned %d\n", kernResult);
     }
 
     int index;
@@ -3343,7 +3349,7 @@
         }
         CFDictionarySetValue(classesToMatch, CFSTR(kIOMediaEjectableKey),
                              kCFBooleanTrue);
-        kernResult = IOServiceGetMatchingServices(masterPort, classesToMatch,
+        kernResult = IOServiceGetMatchingServices(mainPort, classesToMatch,
                                                   mediaIterator);
         if (kernResult != KERN_SUCCESS) {
             error_report("Note: IOServiceGetMatchingServices returned %d",