xnu-4903.270.47.tar.gz

[apple/xnu.git] / bsd / man / man2 / exchangedata.2

diff --git a/bsd/man/man2/exchangedata.2 b/bsd/man/man2/exchangedata.2
index 10a22ae345bc8b3543c9b56421dea9b1ed56c06e..48d05b6c8f8f0268231e3c85c5b754b0547a89f2 100644 (file)
--- a/bsd/man/man2/exchangedata.2
+++ b/bsd/man/man2/exchangedata.2
@@ -73,6 +73,16 @@ Programs that reference the file via an object identifier will continue to
 reference the original file, but now it has the new data.
 .Pp
 .
+WARNING: This system call is largely supported only by HFS and AFP file systems.  Many other
+file systems, including APFS, do not support it.  Further, it is not supported on iOS, tvOS, or watchOS. 
+It is recommended that callers refer
+instead to 
+.Fn rename
+or
+.Fn renamex_np
+to conduct safe-save operations instead. 
+.Pp
+.
 .\" path1 and path2 parameters
 .
 The
@@ -115,6 +125,7 @@ is set to indicate the error.
 .Sh COMPATIBILITY
 Not all volumes support 
 .Fn exchangedata .
+This includes APFS volumes.
 You can test whether a volume supports 
 .Fn exchangedata 
 by using