x/sys/unix: failing tests on android and iOS

[tklauser]

The tests in the vendored copy of golang.org/x/sys/unix (through https://golang.org/cl/112436) fail on android and iOS.

android:

https://build.golang.org/log/ad205265eb82b05e15ce4484f31ead3d7882ed02

--- FAIL: TestPpoll (0.00s)
	syscall_unix_test.go:567: mktmpfifo: failed to create FIFO: permission denied
--- FAIL: TestPoll (0.00s)
	syscall_unix_test.go:567: mktmpfifo: failed to create FIFO: permission denied
--- FAIL: TestGetwd (0.00s)
	syscall_unix_test.go:447: Chdir: chdir /usr/bin: no such file or directory
--- FAIL: TestFchmodat (0.00s)
	syscall_unix_test.go:541: Fchmodat: unexpected error: operation not supported

iOS, added after #25535 (comment):

https://build.golang.org/log/3503d3c0543b005b00f6d7dc2f5ff9844376ceea

--- FAIL: TestDevices (0.00s)
    --- FAIL: TestDevices//dev/ttyp0_4:0 (0.00s)
    	dev_darwin_test.go:35: failed to stat device: operation not permitted
    --- FAIL: TestDevices//dev/ttys0_4:48 (0.00s)
    	dev_darwin_test.go:35: failed to stat device: no such file or directory
    --- FAIL: TestDevices//dev/ptyp0_5:0 (0.00s)
    	dev_darwin_test.go:35: failed to stat device: operation not permitted
    --- FAIL: TestDevices//dev/ptyr0_5:32 (0.00s)
    	dev_darwin_test.go:35: failed to stat device: no such file or directory
--- FAIL: TestPassFD (0.00s)
	syscall_unix_test.go:159: child process: "", fork/exec /var/containers/Bundle/Application/24E1B73D-9932-4B0A-ADAD-44DE6672CC02/gotest.app/gotest: operation not permitted
--- FAIL: TestPoll (0.00s)
	syscall_unix_test.go:567: mktmpfifo: failed to create FIFO: operation not permitted

/cc @hyangah

[gopherbot]

Change https://golang.org/cl/114395 mentions this issue: unix: fix or skip failing tests on android

[tklauser]

On android/{arm,arm64}, also TestDevices and TestSchedSetaffinity fail in addition to the already mentioned tests:

https://build.golang.org/log/064fd97a14c0995ace8d4e2cc978a8b0814ddea0

--- FAIL: TestDevices (0.00s)
    --- FAIL: TestDevices//dev/full_1:7 (0.00s)
    	dev_linux_test.go:36: failed to stat device: permission denied
--- FAIL: TestPpoll (0.00s)
	syscall_unix_test.go:567: mktmpfifo: failed to create FIFO: permission denied
--- FAIL: TestSchedSetaffinity (0.00s)
	syscall_linux_test.go:265: SchedSetaffinity: invalid argument
--- FAIL: TestPoll (0.00s)
	syscall_unix_test.go:567: mktmpfifo: failed to create FIFO: permission denied
--- FAIL: TestGetwd (0.00s)
	syscall_unix_test.go:447: Chdir: chdir /usr/bin: no such file or directory
--- FAIL: TestFchmodat (0.00s)
	syscall_unix_test.go:541: Fchmodat: unexpected error: operation not supported

[tklauser]

/cc @eliasnaur

[eliasnaur]

Some tests fail on iOS as well:

https://build.golang.org/log/3503d3c0543b005b00f6d7dc2f5ff9844376ceea

[tklauser]

Thanks. The TestDevices failures should be gone with https://golang.org/cl/114396. I'll send a fix for the others.

[gopherbot]

Change https://golang.org/cl/114396 mentions this issue: unix: delete TestDevices for *BSD and Darwin

[gopherbot]

Change https://golang.org/cl/114415 mentions this issue: ssh/terminal: fix TestMakeRawState on iOS

[gopherbot]

Change https://golang.org/cl/114416 mentions this issue: cmd/vendor/golang/x: pick up upstream fixes for broken android and iOS tests