Catch low-level unix errors from seek/read/write and wrap in `Error

This avoids low-level errors bubbling up and leaking through the
error handling code in the layer above.

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
write should return Is_read_only if the fd is read-only

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Unknown errors: include the filename as well as the offset/length

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Merge pull request #4 from samoht/master

Fix OSX support
Merge pull request #3 from djs55/improve-error-handling

Catch low-level unix errors from seek/read/write and wrap in `Error
Adapt to newer mirage-types V1.BLOCK.CLIENT type
Merge pull request #5 from avsm/fix-block-types

Adapt to newer mirage-types V1.BLOCK.CLIENT type
Use the external Io_page allocator
Regenerate OASIS

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Merge pull request #6 from djs55/use-io-page

Use Io_page from external repo
Rename ocamlfind package to mirage-block-unix
Regenerate OASIS

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Don't pack the single module into another module
Regenerate OASIS

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Merge pull request #7 from djs55/ocamlfind

Change ocamlfind name to mirage-block-unix
Merge pull request #8 from djs55/ocamlfind

Don't pack the single module into another module
Rename mirage_block to mirage_block_unix

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Merge pull request #9 from djs55/adjust-ocamlfind

Rename mirage_block to mirage_block_unix
Adapt for mirage-types interface changes in mirage/mirage-types@e0b71a665c173a1238b03e4fff3d493d78b4928d
Bump to 0.9.0