title: warning: ignoring return value of 'system' c
body: <p>In my program I put this code for instructs program to spawn a command. This can be used to start another program using a key in my program, such as to spawn firefox. Using program-command run_command "firefox" will have program call system( "firefox &amp;" ). </p>
  
  <pre><code>    case RUN_COMMAND:
          if( arg ) {
              char commandline[ 256 ];
              snprintf( commandline, sizeof (commandline), "%s &amp;", arg );
              if( cmd-&gt;screen ) {
                  char message[ 256 ];
                  snprintf( message, sizeof (message), _("Running: %s"), arg );
                  screen_show_message( cmd-&gt;screen, message );
              }
              system( commandline );
          }
          break;
  </code></pre>
  
  <p>When I compile it give this error:</p>
  
  <pre><code>warning: ignoring return value of 'system', declared with attribute warn_unused_result [-Wunused-result]
  </code></pre>