Permission denied (fork/exec)

[Roberto_Campos]

Hello, I’m trying
to execute this code:

package main

import (
	"fmt"
	"log"
	"uci"
)

func main() {
	eng, err := uci.NewEngine("./Stockfish-master/src")
	if err != nil {
		log.Fatal(err)
	}
	
	// set some engine options
	eng.SetOptions(uci.Options{
		Hash:128,
		Ponder:false,
		OwnBook:true,
		MultiPV:4,
	})

	// set the starting position
	eng.SetFEN("rnb4r/ppp1k1pp/3bp3/1N3p2/1P2n3/P3BN2/2P1PPPP/R3KB1R b KQ - 4 11")
	
	// set some result  filter options
	resultOpts :=  uci.HighestDepthOnly | uci.IncludeUpperbounds |  uci.IncludeLowerbounds
	results,_ := eng.GoDepth(10, resultOpts)

	// print it
	fmt.Println(results)
}

This code calls:

package uci

import (
	"bufio"
	"encoding/json"
	"fmt"
	"log"
	"os/exec"
	"sort"
	"strconv"
	"strings"
	"text/scanner"
)

type Engine struct {
	cmd  *exec.Cmd
	stdout *bufio.Reader
	stdin *bufio.Writer
}

// NewEngine returns an Engine it has spun up
// and connected  communication to
func NewEngine(path string) (*Engine, error) {
	eng := Engine{}

   //FAIL IN THIS LINE
	eng.cmd = exec.Command(path)

	stdin, err :=  eng.cmd.StdinPipe()
	if err != nil {
		return nil, err
	}
	stdout, err := eng.cmd.StdoutPipe()
	if err != nil {
		return nil, err
	}
	if err := eng.cmd.Start(); err != nil {
		return nil, err
	}
	eng.stdin = bufio.NewWriter(stdin)
	eng.stdout = bufio.NewReader(stdout)
	return &eng, nil
}

When I execute I have the following problem:

2016/07/18 22:16:12 fork/exec ./Stockfish-master/src: permission denied

I execute the program as sudo (sudo ./execute), but I have the same result.
My version of Go is: go version go1.6.2 linux/amd64
I don’t know why my program doesn’t enough permissions to execute this command.
This program is UCI which communicate with Stockfish (Chess engine)

Many thanks in advance.

[calmh (Jakob Borg)]

@Roberto_Campos

fork/exec ./Stockfish-master/src: permission denied

Is this in fact the path to your executable, and if so what are the permissions on it?

ls -l ./Stockfish-master/src

[sulhan]

Probably “”./Stockfish-master/src" is a directory. AFAIK (in other programming language), exec must point to executable file.

[Roberto_Campos]

Yes. “./Stockfish-master/src” is a directory. My idea was that my program execute the main class inside of “src”. Now, I know that I need to point to executable file.

Many thanks for your help.