os/exec: disable fd check in TestHelperProcess on Plan 9
On Plan 9, we can observe the following open file descriptors:
0 r c 0 (
000000000000000a 0 00) 0 0 /dev/null
1 rw | 0 (
0000000001df6742 0 00) 65536 54 #|/data1
2 rw | 0 (
0000000001df6782 0 00) 65536 0 #|/data1
3 rw M 1956 (
0000000000d66dd2 0 00) 8192 12 /tmp/
333163398
4 r c 0 (
0000000000000001 0 00) 0 528 /dev/bintime
5 r M 1956 (
0000000000d66dd1 854 00) 8192 0 /tmp/go-build843954301/os/exec/_test/exec.test
6 r M 1956 (
0000000000d66dd1 854 00) 8192 0 /tmp/go-build843954301/os/exec/_test/exec.test
7 r M 1956 (
0000000000d66dd1 854 00) 8192 0 /tmp/go-build843954301/os/exec/_test/exec.test
8 r M 1956 (
0000000000d66dd1 854 00) 8192 0 /tmp/go-build843954301/os/exec/_test/exec.test
9 r M 1956 (
0000000000d66dd1 854 00) 8192 0 /tmp/go-build843954301/os/exec/_test/exec.test
10 r M 1956 (
0000000000d66dd1 854 00) 8192 0 /tmp/go-build843954301/os/exec/_test/exec.test
11 r c 0 (
000000000000000f 0 00) 0 32 /dev/random
12 r M 1956 (
0000000000d66dd1 854 00) 8192 0 /tmp/go-build843954301/os/exec/_test/exec.test
13 r c 0 (
000000000000000a 0 00) 0 0 /dev/null
14 rw | 0 (
0000000001df6801 0 00) 65536 0 #|/data
15 rw | 0 (
0000000001df6802 0 00) 65536 1275 #|/data1
R=rsc, bradfitz, aram
CC=golang-codereviews
https://golang.org/cl/
51420044