HOWTO: Add platforms without fdatasync(2)

Added DragonFlyBSD which is a fork of FreeBSD.
FreeBSD seems to have fdatasync(2) in their upstream, but not yet
in the latest release version if I checked correctly.

Btw, having "Windows" here sounds a bit ambiguous.
Cygwin with gcc (not MinGW) compiles below taken from ./configure
by linking against POSIX compat dll.

--
 $ uname
 CYGWIN_NT-10.0
 $ cat ./fdatasync1.c
 #include <stdio.h>
 #include <unistd.h>
 int main(int argc, char **argv)
 {
 	  return fdatasync(0);
 }
 $ gcc -Wall -g ./fdatasync1.c ; echo $?
 0

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/HOWTO b/HOWTO
index 15ed42549580a659c82cd5febb7e4be6a441addc..7884944a763d55436b365e8ca90c83cfbb9f5505 100644 (file)
--- a/HOWTO
+++ b/HOWTO
@@ -1104,7 +1104,7 @@ I/O type
 .. option:: fdatasync=int
 
        Like :option:`fsync` but uses :manpage:`fdatasync(2)` to only sync data and
-       not metadata blocks.  In FreeBSD and Windows there is no
+       not metadata blocks.  In Windows, FreeBSD, and DragonFlyBSD there is no
        :manpage:`fdatasync(2)`, this falls back to using :manpage:`fsync(2)`.
 
 .. option:: write_barrier=int