go - Golang 中多个程序之间的交互

Question

我正在尝试让两个 golang 程序使用管道进行通信，每个程序同时运行，例如:

1 go run master/main/main.go 

2 master/main/main.go calls slave.exe (built go program)

3 slave.exe prints out "Ping"

4 master/main/main.go reads "Ping" and writes "Pong"

5 slave.exe reads "Pong" and prints out "Message recieved: Pong"

程序到达第 4 步，但没有收到来自 slave.exe 的另一条消息。

在 master/main/main.go 中:

package main

import (
    "fmt"
    "os"
    "os/exec"
    "bufio"
)

func main() {
    // Run compiled slave project:
    c := exec.Command("main", insert_path_to_exe_here)

    out, _ := c.StdoutPipe()
    in, _ := c.StdinPipe()

    c.Start() // Using Start() instead of Run() because Run() waits for program to finish before moving on.

    inwriter := bufio.NewWriter(in)
    outreader := bufio.NewReader(out)

    // This should print "Ping".
    fmt.Println(outreader.ReadString('\n'))

    inwriter.WriteString("Pong")

    // This should print "Message received: Pong"
    fmt.Println(outreader.ReadString('\n'))

}

在 slave/main/main.go 中:

package main

import (
    "fmt"
    "bufio"
    "os"
)

func main() {
    fmt.Println("Ping")
    reader := bufio.NewReader(os.Stdin)

    s, _ := reader.ReadString('\n')

    fmt.Println("Message received: ", s)
}

运行:

• 构建slave/main/main.go
• 将 insert_path_to_exe_here 替换为构建的可执行文件的路径，并将“main”替换为可执行文件的名称。
• 运行 master/main/main.go

Answer 1

您的子进程正在使用 ReadString('\n')，但您没有编写 \n 字符，也没有刷新缓冲的编写器。

这会将预期的数据写入管道:

inwriter.WriteString("Pong\n")
inwriter.Flush()