how to delay the login items to start I use a program to deal with the contents in sd card on startup. But the problem is that the program always starts before I can see the sd card in the finder.  As a result, the program can't find the contents and can't run correctly. I think whether I can delay the startup time of a specified program in login items preference.
Make a simple bash script, that starts on startup instead:

#!/bin/bash
#Wait for however long you want:
sleep &lt;num of seconds&gt;
#Use the following if the program is a .app:
open -a /path/to/app/myApp.app
#Use the following if the program is an executable (not a .app):
/path/to/exec/theExec


Now, save the file to your documents folder as startupScript.bash. 

Note: If you use textedit to create the file, hold down  shift  +  command  +  T  before saving it.

Open up "Terminal". Type:

chmod +x ~/Documents/startupScript.bash

Then open up System Preferences, and add the script to the login items tab.