test: make the example tests pass on macOS

examples/t/.prove

@@ -0,0 +1,64 @@
+---
+generation: 11
+last_run_time: 1789642220.28353
+tests:
+  "./async.t":
+    elapsed: 2.26030302047729
+    gen: 11
+    last_fail_time: 1789642159.55943
+    last_pass_time: 1789642216.66124
+    last_result: 0
+    last_run_time: 1789642216.66124
+    last_todo: 0
+    mtime: 1779628780
+    seq: 54
+    total_failures: 6
+    total_passes: 5
+  "./awssig.t":
+    elapsed: 0.0434160232543945
+    gen: 11
+    last_pass_time: 1789642214.44578
+    last_result: 0
+    last_run_time: 1789642214.44578
+    last_todo: 0
+    mtime: 1789641794
+    seq: 51
+    total_passes: 11
+  "./curl.t":
+    elapsed: 0.251311063766479
+    gen: 11
+    last_fail_time: 1789642159.56034
+    last_pass_time: 1789642214.65495
+    last_result: 0
+    last_run_time: 1789642214.65495
+    last_todo: 0
+    mtime: 1730375785
+    seq: 52
+    total_failures: 6
+    total_passes: 5
+  "./shared_dict.t":
+    elapsed: 5.87828707695007
+    gen: 11
+    last_fail_time: 1789642159.56064
+    last_pass_time: 1789642220.28316
+    last_result: 0
+    last_run_time: 1789642220.28316
+    last_todo: 0
+    mtime: 1789641955
+    seq: 55
+    total_failures: 6
+    total_passes: 5
+  "./upstream.t":
+    elapsed: 0.262914180755615
+    gen: 11
+    last_fail_time: 1789642159.56518
+    last_pass_time: 1789642214.71092
+    last_result: 0
+    last_run_time: 1789642214.71092
+    last_todo: 0
+    mtime: 1730375785
+    seq: 53
+    total_failures: 6
+    total_passes: 5
+version: 1
+...

examples/t/awssig.t

@@ -21,6 +21,11 @@ use Test::Nginx;
 select STDERR; $| = 1;
 select STDOUT; $| = 1;
 
+# The example is not built on Darwin: chrono reaches the local timezone
+# through CoreFoundation, which is not fork-safe.  See examples/config.
+plan(skip_all => 'awssig example is not built on this platform')
+	if $^O eq 'darwin';
+
 my $t = Test::Nginx->new()->has(qw/http proxy/)->plan(1)
 	->write_file_expand('nginx.conf', <<"EOF");
 

examples/t/shared_dict.t

@@ -108,7 +108,12 @@ sub check {
 
 	my $pid = $1;
 
-	for (1 .. 25) {
+	for (1 .. 60) {
+		# Back-to-back requests keep landing on the worker that is
+		# already awake.  Pause so the kernel has a reason to wake
+		# the other one.
+		select(undef, undef, undef, 0.2);
+
 		$r = http_get($uri);
 
 		return unless ($r =~ $like && $r =~ /X-Process: (\d+)/);