:manpage:`read(2)` and :manpage:`write(2)` for asynchronous
I/O. Requires :option:`filename` option to specify either block or
character devices.
+ The sg engine includes engine specific options.
**null**
Doesn't transfer any data, just pretends to. This is mainly used to
multiple paths exist between the client and the server or in certain loopback
configurations.
+.. option:: readfua=bool : [sg]
+
+ With readfua option set to 1, read operations include
+ the force unit access (fua) flag. Default is 0.
+
+.. option:: writefua=bool : [sg]
+
+ With writefua option set to 1, write operations include
+ the force unit access (fua) flag. Default is 0.
+
+
I/O depth
~~~~~~~~~