Spawning process _ golang

Sometimes our Go programs need to spawn other, non-Go process. For example, the syntax highlighting on this site is implemented by spawning a pygmentize process from a Go program. Let‘s look at a few examples of spawning processes from Go

package main

import (
    "fmt"
    "io/ioutil"
    "os/exec"
)

func main() {

    dateCmd := exec.Command("date")

    dateOut, err := dateCmd.Output()
    if err != nil {
        panic(err)
    }

    fmt.Println("> date")
    fmt.Println(string(dateOut))

    grepCmd := exec.Command("grep", "hello")

    grepIn, _ := grepCmd.StdinPipe()
    grepOut, _ := grepCmd.StdoutPipe()
    grepCmd.Start()
    grepIn.Write([]byte("hello grep\ngoodbye grep"))
    grepIn.Close()
    grepBytes, _ := ioutil.ReadAll(grepOut)
    grepCmd.Wait()

    fmt.Println("> grep hello")
    fmt.Println(string(grepBytes))

    lsCmd := exec.Command("bash", "-c", "ls -a -l -h")
    lsOut, err := lsCmd.Output()
    if err != nil {
        panic(err)
    }

    fmt.Println("> ls -a -l -h")
    fmt.Println(string(lsOut))
}
> date
Wed Apr  1 13:15:32 CST 2015

> grep hello
hello grep

> ls -a -l -h
total 3648
drwxr-xr-x  16 xjk  staff   544B Apr  1 13:09 .
drwxr-xr-x+ 30 xjk  staff   1.0K Mar  6 14:00 ..
[email protected]  1 xjk  staff   6.0K Mar 27 11:21 .DS_Store
-rw-r--r--   1 xjk  staff   838B Mar 30 13:38 Reading.go
-rw-r--r--   1 xjk  staff   553B Mar 27 13:12 URL.go
-rw-r--r--   1 xjk  staff   598B Mar 30 13:45 Writing.go
-rw-r--r--   1 xjk  staff   402B Mar 30 13:23 base64.go
-rw-r--r--   1 xjk  staff   447B Mar 31 13:28 commandLineFlags.go
-rwxr-xr-x   1 xjk  staff   1.7M Mar 31 13:21 commonLineArgument
-rw-r--r--   1 xjk  staff   209B Mar 31 13:20 commonLineArgument.go
-rw-r--r--   1 xjk  staff   261B Apr  1 13:02 environmentVariables.go
-rw-r--r--   1 xjk  staff   298B Mar 31 13:15 lineFilters.go
-rw-r--r--   1 xjk  staff   384B Mar 27 13:04 number_parsing.go
-rw-r--r--   1 xjk  staff   189B Mar 27 13:18 sha.go
-rw-r--r--   1 xjk  staff   720B Apr  1 13:15 spawningProcess.go
-rwxr-xr-x   1 xjk  staff   243B Mar 27 11:25 urllib001.p

总结 :

　　1 : ...

时间： 2024-10-18 21:09:38

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