PHP page Jump cannot get session value

Write the project today, you need to get session value on the page after the jump to automatic login operation, but obviously in the transmission page can print out the session value, but in the acceptance page is displayed the session value is empty, confirmed that the script session_start () is open, and accept the code is not a problem, finally found that the problem in the domain name, the transmission page domain name is different, and the session cross-domain value needs other settings, the problem is low-level, but should be warning, code writing is a rigorous work, sloppy, in the future code should be particularly careful in writing.

PHP page Jump cannot get session value