Description:
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PHP sessions will hang if an external command is executed either through system() or the popen() calls. The session restores as soon as the external command terminates. The problem is when I try to follow another link in a multiframed view.



Reproduce code:
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session_start();
.....
.....

set_time_limit(0);
ignore_user_abort(TRUE);
system($cmd, $sys_res); // Takes very long

.....

note (I tried popen aswell)

Expected result:
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does not matter

Actual result:
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does not matter