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-rw-r--r--src/cmd/cgo/internal/teststdio/testdata/fib.go50
1 files changed, 50 insertions, 0 deletions
diff --git a/src/cmd/cgo/internal/teststdio/testdata/fib.go b/src/cmd/cgo/internal/teststdio/testdata/fib.go
new file mode 100644
index 0000000..9617368
--- /dev/null
+++ b/src/cmd/cgo/internal/teststdio/testdata/fib.go
@@ -0,0 +1,50 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build test_run
+
+// Compute Fibonacci numbers with two goroutines
+// that pass integers back and forth. No actual
+// concurrency, just threads and synchronization
+// and foreign code on multiple pthreads.
+
+package main
+
+import (
+ "runtime"
+ "strconv"
+
+ "cgostdio/stdio"
+)
+
+func fibber(c, out chan int64, i int64) {
+ // Keep the fibbers in dedicated operating system
+ // threads, so that this program tests coordination
+ // between pthreads and not just goroutines.
+ runtime.LockOSThread()
+
+ if i == 0 {
+ c <- i
+ }
+ for {
+ j := <-c
+ stdio.Stdout.WriteString(strconv.FormatInt(j, 10) + "\n")
+ out <- j
+ <-out
+ i += j
+ c <- i
+ }
+}
+
+func main() {
+ c := make(chan int64)
+ out := make(chan int64)
+ go fibber(c, out, 0)
+ go fibber(c, out, 1)
+ <-out
+ for i := 0; i < 90; i++ {
+ out <- 1
+ <-out
+ }
+}