In case we have stdin redirected, we still have a terminal which
can be obtained from stdout or stderr. This is what this commit
does.

This should allow something like this to work:

> ctr run --rm --tty docker.io/library/hello-world:latest xxx < /dev/null

NB: in case all three are redirected, but we still have a controlling
tty, we can easily get it by opening /dev/tty, but then it should be
closed, and it's not quite clear by whom and when, so this is left as
a home exersize for the reader.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

Current: allow stdin to be redirected

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

Use unix.IoctlSetPointerInt instead of manually implementing it. This
fixes the build on darwin where direct syscalls, i.e.
unix.Syscall(SYS_IOCTL, ...) are no longer allowed and exported as of
golang/sys@6fcdbc0

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

Use IoctlSetPointerInt from golang.org/x/sys/unix

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Also add linting to CI and remove travis script entries that were no-ops
(there are no tests for other platforms so the extra `go test`
invocations with GOOS settings were not doing anything)

Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com>

vendor: pkg/errors v0.9.1

Enable Github Actions-based CI

Getting the golangci-lint package needs to be done with the gomod
method.

Signed-off-by: Phil Estes <estesp@linux.vnet.ibm.com>

Fix actions to follow the model from other repos

Use unix.IoctlSetPointerInt and unix.IoctlGetInt instead of manually
implementing them. This avoid the use of the `unsafe` package.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>

Now that we have GitHub actions running, the travis configuration
file should no longer be needed.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Remove travis configuration file

Signed-off-by: Leonardo Taccari <leot@NetBSD.org>

Add support for NetBSD

Use Ioctl{SetPointerInt,GetInt} from golang.org/x/sys/unix on linux