os.Create“打开的文件太多”

Question

I have around 220'000 image files (.png) to create. I run into this error message when trying to create the 1'081th file: panic: open /media/Snaps/pics/image1081_0.png: too many open files

I've added the defer w.Close() line but it did not change the error.

    i := 1
    for i <= 223129 {

    (some other code to prepare the data and create the chart)

    img := vgimg.New(450, 600)
    dc := draw.New(img)

    canvases := table.Align(plots, dc)
    plots[0][0].Draw(canvases[0][0])
    plots[1][0].Draw(canvases[1][0])
    plots[2][0].Draw(canvases[2][0])


    testFile := "/media/Snaps/pics/image"+strconv.Itoa(i+60)+"_"+gain_loss+".png"

        w, err := os.Create(testFile)
        if err != nil {
            panic(err)
        }
        defer w.Close()

        png := vgimg.PngCanvas{Canvas: img}
        if _, err := png.WriteTo(w); err != nil {
            panic(err)
        }   

        //move to next image
        i = i + 1
     }

Surely this limit can be worked around ? Maybe I'm not closing the files properly ?

Answer 1

ok, i got it, changed defer w.Close() to w.Close() and moved it after

png := vgimg.PngCanvas{Canvas: img}
if _, err := png.WriteTo(w); err != nil {
      panic(err)
}

I'm now above 10'000 images and running...