exec.Command with options list
bdentremont
cd /tmp/2013-08-29_16.54.51.432786
mencoder "mf://*.png" -o movie.avi -ovc x264
I get what I want. However, when I attempt to call the shell command in Go, I get the following error:
"MEncoder svn r34540 (Ubuntu), built with gcc-4.6 (C) 2000-2012 MPlayer Team
Exiting... (No output file specified, please see the -o option.)"
package main
import (
"fmt"
"os/exec"
)
func main() {
cmd := exec.Command(`mencoder`, `mf://*.png -o movie.avi -ovc x264`)
//cmd := exec.Command(`ls`, `-la`)
//cmd := exec.Command(`ls`, `-l`, `-a`)
cmd.Dir = "/tmp/2013-08-29_16.54.51.432786"
out, _ := cmd.CombinedOutput()
fmt.Println(string(out))
}
Rémy Oudompheng
> like this to happen automatically after running my Go program. If I run
> from the bash shell,
>
> cd /tmp/2013-08-29_16.54.51.432786
> mencoder "mf://*.png" -o movie.avi -ovc x264
>
> I get what I want. However, when I attempt to call the shell command in Go,
> I get the following error:
>
> "MEncoder svn r34540 (Ubuntu), built with gcc-4.6 (C) 2000-2012 MPlayer Team
>
> Exiting... (No output file specified, please see the -o option.)"
>
>
> Both the commented "ls" commands in the following code work properly and the
> output verifies that I'm in the right directory. Can someone point me in
> the direction of what I'm missing?
>
> package main
>
> import (
> "fmt"
> "os/exec"
> )
>
> func main() {
> cmd := exec.Command(`mencoder`, `mf://*.png -o movie.avi -ovc x264`)
-ovc x264". Do you have a file named like that?
Rémy.
bdentremont
This command calls mencoder on a file named "mf://*.png -o movie.avi
-ovc x264". Do you have a file named like that?
Rémy.
Rémy:
Thank you for your advice. I indeed do not have a file by that name. However, I also do not have one by the name "-la" nor "hello" yet "exec.Command(`ls`, `-la`)" and the example given in the "os/exec" documentation "exec.Command("echo", "hello")" both work fine. Is there a reason that one would get interpreted as a file path and the other passed as string? This may be obvious to you via your experience in other languages, but I'm a novice programmer trying to learn.
Brian
Sebastien Binet
sent from my droid
On Aug 29, 2013 6:18 PM, "bdentremont" <bdent...@gmail.com> wrote:
>
> I'm trying to combine some plots in PNG into a movie on Ubuntu. I would like this to happen automatically after running my Go program. If I run from the bash shell,
>
> cd /tmp/2013-08-29_16.54.51.432786
> mencoder "mf://*.png" -o movie.avi -ovc x264
>
> I get what I want. However, when I attempt to call the shell command in Go, I get the following error:
>
> "MEncoder svn r34540 (Ubuntu), built with gcc-4.6 (C) 2000-2012 MPlayer Team
>
> Exiting... (No output file specified, please see the -o option.)"
>
>
> Both the commented "ls" commands in the following code work properly and the output verifies that I'm in the right directory. Can someone point me in the direction of what I'm missing?
>
> package main
>
> import (
> "fmt"
> "os/exec"
> )
>
> func main() {
> cmd := exec.Command(`mencoder`, `mf://*.png -o movie.avi -ovc x264`)
This should read:
cmd := exec.Command(`mencoder`, `mf://*.png', '-o', 'movie.avi', 'x264`)
With double quotes all along.
-s
> //cmd := exec.Command(`ls`, `-la`)
> //cmd := exec.Command(`ls`, `-l`, `-a`)
> cmd.Dir = "/tmp/2013-08-29_16.54.51.432786"
> out, _ := cmd.CombinedOutput()
> fmt.Println(string(out))
> }
>
> --
> You received this message because you are subscribed to the Google Groups "golang-nuts" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts...@googlegroups.com.
> For more options, visit https://groups.google.com/groups/opt_out.
bdentremont
Sebastien:
Thank you, but I get exactly the same error with that as well.
Brian
package main
import (
"fmt"
"os/exec"
)
func main() {
fmt.Println(string(out))
}
MEncoder svn r34540 (Ubuntu), built with gcc-4.6 (C) 2000-2012 MPlayer Team
Exiting... (No output file specified, please see the -o option.)
Brad Fitzpatrick
--
Brad Fitzpatrick
--
bdentremont
I'm aware of that. My original attempt at this paniced on error. Yet, it seemed that the shell output, not the exit status characterized my problem.
You are, of course, entirely right about the quote issue. I'd cut and pasted a previous reply and didn't see that. As things currently stand:
package main
import (
"fmt"
"os/exec"
)
func main() {
cmd := exec.Command(`mencoder`, `"mf://*.png"`, `-o`, `movie.avi`, `x264`)
out, err := cmd.CombinedOutput()
fmt.Println(string(out))
if err != nil {
panic(err)
}
}
MEncoder svn r34540 (Ubuntu), built with gcc-4.6 (C) 2000-2012 MPlayer Team
No stream found to handle url "mf://*.png"
Cannot open file/device.
Exiting...
panic: exit status 1
goroutine 1 [running]:
main.main()
/home/brian/go/src/bdentremont/tmp/main.go:15 +0x186
goroutine 2 [syscall]:
created by runtime.main
/build/buildd/golang-1/src/pkg/runtime/proc.c:221
Error: process exited with code 2.
Brad Fitzpatrick
bdentremont
Brian
import (
"fmt"
"os/exec"
)
func main() {