Commit d39fbe8

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README.md
go-37
- unsafe_test.go

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`‎README.md`

Lines changed: 1 addition & 1 deletion

Original file line number	Diff line number	Diff line change
`@@ -81,7 +81,7 @@ ps:白天上班,晚上更新,尽量日更,比心`
`81`	`81`
`82`	`82`	`[第36章万能程序](https://github.com/java-aodeng/golang-examples/blob/master/go-36/flexible_reflect_test.go)`
`83`	`83`
`84`		`-第37章不安全编程`
	`84`	`+[第37章不安全编程](https://github.com/java-aodeng/golang-examples/blob/master/go-37/unsafe_test.go)`
`85`	`85`
`86`	`86`	`第38章实现pipe-filter framework`
`87`	`87`

`‎go-37/unsafe_test.go`

Lines changed: 68 additions & 0 deletions

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,68 @@`
	`1`	`+package go_37`
	`2`	`+`
	`3`	`+import (`
	`4`	`+ "fmt"`
	`5`	`+ "sync"`
	`6`	`+ "sync/atomic"`
	`7`	`+ "testing"`
	`8`	`+ "time"`
	`9`	`+ "unsafe"`
	`10`	`+)`
	`11`	`+`
	`12`	`+/*`
	`13`	`+不安全编程`
	`14`	`+`
	`15`	`+- go语言是不持支强制类型转换的`
	`16`	`+*/`
	`17`	`+`
	`18`	`+func TestUnsafe(t *testing.T) {`
	`19`	`+ i := 10`
	`20`	`+ f := (float64)(unsafe.Pointer(&i))`
	`21`	`+ t.Log(unsafe.Pointer(&i))`
	`22`	`+ t.Log(f)`
	`23`	`+}`
	`24`	`+`
	`25`	`+/* 运行结果,可以看到一个10强制类型转换后值变成了5e-323,所有go是不能这样写的,没java方便`
	`26`	`+=== RUN TestUnsafe`
	`27`	`+ unsafe_test.go:17: 0xc00000a370`
	`28`	`+ unsafe_test.go:18: 5e-323`
	`29`	`+--- PASS: TestUnsafe (0.00s)`
	`30`	`+PASS`
	`31`	`+*/`
	`32`	`+`
	`33`	`+//原子类型操作`
	`34`	`+func TestAtomic(t *testing.T) {`
	`35`	`+ var shareBufPtr unsafe.Pointer`
	`36`	`+ writeDataFn := func() {`
	`37`	`+ data := []int{}`
	`38`	`+ for i := 0; i < 100; i++ {`
	`39`	`+ data = append(data, i)`
	`40`	`+ }`
	`41`	`+ atomic.StorePointer(&shareBufPtr, unsafe.Pointer(&data))`
	`42`	`+ }`
	`43`	`+ readDataFn := func() {`
	`44`	`+ data := atomic.LoadPointer(&shareBufPtr)`
	`45`	`+ fmt.Println(data, ([]int)(data))`
	`46`	`+ }`
	`47`	`+ var wg sync.WaitGroup`
	`48`	`+ writeDataFn()`
	`49`	`+ for i := 0; i < 10; i++ {`
	`50`	`+ wg.Add(1)`
	`51`	`+ go func() {`
	`52`	`+ for i := 0; i < 10; i++ {`
	`53`	`+ writeDataFn()`
	`54`	`+ time.Sleep(time.Microsecond * 100)`
	`55`	`+ }`
	`56`	`+ wg.Done()`
	`57`	`+ }()`
	`58`	`+ wg.Add(1)`
	`59`	`+ go func() {`
	`60`	`+ for i := 0; i < 10; i++ {`
	`61`	`+ readDataFn()`
	`62`	`+ time.Sleep(time.Microsecond * 100)`
	`63`	`+ }`
	`64`	`+ wg.Done()`
	`65`	`+ }()`
	`66`	`+ }`
	`67`	`+ wg.Wait()`
	`68`	`+}`

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Commit d39fbe8

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`‎README.md`

`‎go-37/unsafe_test.go`

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