go - In golang how can I write the stdout of an exec.Cmd to a file? -

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i trying run shell command, capture stdout , write output file. however, seem missing few steps, file trying write empty when program exists. how can capture stdout of command , write file?

package main  import (     "bufio"     "io"     "os"     "os/exec" )  func main() {      cmd := exec.command("echo", "'what heck up'")      // open out file writing     outfile, err := os.create("./out.txt")     if err != nil {         panic(err)     }     defer outfile.close()      stdoutpipe, err := cmd.stdoutpipe()     if err != nil {         panic(err)     }      writer := bufio.newwriter(outfile)      err = cmd.start()     if err != nil {         panic(err)     }      go io.copy(writer, stdoutpipe)     cmd.wait() }

you need flush writer. add following:

    writer := bufio.newwriter(outfile)     defer writer.flush()

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