Re: [Libguestfs] [nbdkit PATCH v2 2/2] sh: Add exit status triggers for nbdkit_{shutdown, disconnect}

Make it possible for the sh and eval plugins to disconnect a client or shut down the entire nbdkit server by use of special return values. Prior to this patch we had reserved 4-7 for future use; this defines 4-8, and extends the set of reserved return values to 9-15. We figure it is unlikely that anyone is using status 4-15 with the intent that it behaves identically to status 1; more importantly, the choice of soft disconnect with error for status 8 is the one least likely to break such an existing sh or eval script. For the testsuite, I only covered the eval plugin; but since it shares common code with the sh plugin, both styles should work. A note about the pod documentation: when the argument to =item would otherwise appear to be a single number, the use of S<> to mask it is necessary. ---

+=item 9-15 + +These exit codes are reserved for future use. Note that versions of +nbdkit E<lt> 1.34 documented that codes S<8> through S<15> behaved +like code S<1>; although it is unlikely that many scripts relied on +this similarity in practice.