GTK+ system(3) call with thread

Question

I developed a simple application with GTK+-2.0. My question is how can run a bash script (for example with system(3)) without freezing program? I tried to implement a thread system but it did not worked.

Here is my code snippet, I tried to simplify as good as I can. Regards

int main(int argc,
    char * argv[])
{
    GtkWidget *button;


    /* init threads */  
    g_thread_init(NULL);
    gdk_threads_init();
    gtk_init(&argc,&argv);

    window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
    ...

    button = gtk_button_new_with_label("Format");
    g_signal_connect(button,"clicked",G_CALLBACK(callback),(gpointer)"button 1");
    gtk_table_attach_defaults (GTK_TABLE (table), button, 0, 1, 0, 1);
    gtk_widget_show(button);


        gdk_threads_enter();
    gtk_main();
    gdk_threads_leave();

    return 0;

}

/* Our callback.
* The data passed to this function is printed to stdout */
static void callback( GtkWidget *widget,
                  gpointer   data )
{
    int sTemp=0;
    GThread   *thread;
        GError    *error = NULL;
        g_print ("Hello again - %s was pressed\n", (char *) data);
        sTemp=ChecckIfFileExits("/dev/mmcblk0");
        if(sTemp)
        {
        gtk_label_set_text(GTK_LABEL(label),"Formatting");
        thread = g_thread_create( PFormatThrad, (gpointer)widget,
                          FALSE, &error );
        if( ! thread )
        {
            g_print( "Error: %s\n", error->message );

        }

    }
    else
    {
        g_print ("SD/MMC not found\n");
    }
}


static gpointer
PFormatThrad( gpointer data )
{

        sleep( 3 );

        gdk_threads_enter();

        system("./mkcard.txt /dev/mmcblk0");
    gtk_widget_set_sensitive(selectImageButton,TRUE);
    gtk_label_set_text(GTK_LABEL(label),"Format tamamlandı\nİmajı Seçin");
        gdk_threads_leave();

    return( NULL );
}    

Answer 1

Don't call fork() directly.

It's better, in a GTK+ application, to use glib's process spawning API:s . For instance the g_spawn_async_with_pipes() function is very handy if you want to read the child process' output.

Answer 2

Try forking your process and start the bash script in the forked process.

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>

int main ()
{
   int pid;

   pid = fork();

   if (pid == 0) {
      // Call bash script
   } else if (pid > 0) {
     // Your parent process
   }
   return 0;
}