search for: never_used1

...unt, uint64_t offset); #endif int (*flush) (void *handle); int (*trim) (void *handle, uint32_t count, uint64_t offset); int (*zero) (void *handle, uint32_t count, uint64_t offset, int may_trim); int errno_is_preserved; void (*dump_plugin) (void); #if NBDKIT_PLUGIN_LEVEL <= 1 int (*never_used1) (void *handle, const void *buf, uint32_t count, uint64_t offset, unsigned flags); #else int (*pwrite) (void *handle, const void *buf, uint32_t count, uint64_t offset, unsigned flags); #endif (3) Core nbdkit code always defines NBDKIT_PLUGIN_LEVEL == 2 so that it always sees the new function, b...

Tested via: term1$ qemu-nbd -k $PWD/sock -t -f raw -x foo junk --trace=nbd_\* term2$ ./nbdkit -f -v -e bar nbd socket=$PWD/sock export=foo term3$ qemu-io -t none -f raw nbd://localhost:10809/bar --trace=nbd_\* and checking the traces to see that 'w 0 1' vs. 'w -f 0 1' was able to influence whether the FUA flag showed up at the server in term1. Still to go: figure out how to