tests: aix: avoid unsupported functionality

* tests/misc/tee.sh: AIX doesn't support detecting
closed outputs either with poll() or select() so avoid
testing that functionality.
* tests/tail-2/pipe-f.sh: Likewise.

tests/misc/tee.sh

@@ -63,6 +63,9 @@ if test -w /dev/full && test -c /dev/full; then
   test $(wc -l < err) = 1 || { cat err; fail=1; }
 fi
 
+case $host_triplet in
+  *aix*) echo  'avoiding due to no way to detect closed outputs on AIX' ;;
+  *)
 # Test iopoll-powered early exit for closed pipes
 tee_exited() { sleep $1; test -f tee.exited; }
 # Currently this functionality is most useful with
@@ -72,7 +75,8 @@ tee_exited() { sleep $1; test -f tee.exited; }
 retry_delay_ tee_exited .1 7 | # 12.7s (Must be > following timeout)
 { timeout 10 tee -p 2>err && touch tee.exited; } | :
 test $(wc -l < err) = 0 || { cat err; fail=1; }
-test -f tee.exited || fail=1
+test -f tee.exited || fail=1 ;;
+esac
 
 # Test with unwriteable files
 touch file.ro || framework_failure_

tests/tail-2/pipe-f.sh

@@ -41,6 +41,9 @@ compare exp out || fail=1
 # Also check tail exits if SIGPIPE is being ignored.
 # Note 'trap - SIGPIPE' is ineffective if the initiating shell
 # has ignored SIGPIPE, but that's not the normal case.
+case $host_triplet in
+  *aix*) echo  'avoiding due to no way to detect closed outputs on AIX' ;;
+  *)
 for disposition in '' '-'; do
   (trap "$disposition" PIPE;
    returns_ 124 timeout 10 \
@@ -49,7 +52,8 @@ for disposition in '' '-'; do
   test -e timed_out && fail=1
   compare exp out2 || fail=1
   rm -f timed_out
-done
+done ;;
+esac
 
 # This would wait indefinitely before v8.28 (until first write)
 # test -w /dev/stdout is used to check that >&- is effective