What is the best way to find out (in a script) whether SElinux is used?

[Aleksey Nogin <aleksey nogin org>]

I want to have a script that acts slightly differently depending on 
whether SELinux is being used or not. What is the best way to do it?

My initial attempts to use "-e /etc/security/selinux" or "-e 
/selinux/enforce" all create log messages:

audit(1079689937.170:0): avc:  denied  { getattr } for  pid=2662 
exe=/bin/bash path=/etc/security/selinux dev=hda2 ino=3712021 
scontext=aleksey:staff_r:staff_t 
tcontext=system_u:object_r:policy_config_t tclass=dir
audit(1079690744.526:0): avc:  denied  { getattr } for  pid=3577 
exe=/bin/bash path=/selinux/enforce dev= ino=4 
scontext=aleksey:staff_r:staff_t tcontext=system_u:object_r:security_t 
tclass=file

--
Aleksey Nogin

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