!!! Overview
[{$pagename}] is about determining the [version] of various [Operating System] ([OS])

!![AIX]
{{{
oslevel -s
5300-06-01-0000
}}}

!! [Solaris]
I always find [Solaris versions] confusing.
{{{
uname -a
}}}

Or 
{{{
showrev -a

Hostname: starbug
Hostid: nnnnnnnn
Release: 5.9
Kernel architecture: sun4u
Application architecture: sparc
Hardware provider: Sun_Microsystems
Domain: solar.com
Kernel version: SunOS 5.9 May 2002

OpenWindows version: 
X11 Version 6.4.2 11 April 2001

No patches are installed
}}}

!! [Linux] 
Usually you can get the kernel version form:
{{{
uname -a
}}}

Most [Linux] [versions] have additional information on the version.
{{{
 uname -a
Linux francis 2.6.16.21-0.8-smp #1 SMP Mon Jul 3 18:25:39 UTC 2006 i686 athlon i386 GNU/Linux
}}}

! THis works with MOST [Linux] [versions] and provides vendor specific information
%%prettify 
{{{
cat /etc/**release**
}}} 
/%

! [SuSE]
On SUSE try this for more details:
{{{
cat /etc/SuSE-release

SUSE Linux Enterprise Server 10 (i586)
VERSION = 10
}}}

And someone said:
{{{
# cat /etc/issue

Welcome to SUSE Linux Enterprise Server 10 (i586) - Kernel \r (\l).
}}}

!Redhat
{{{
$ cat /etc/redhat-release
Red Hat Enterprise Linux AS release 3 (Taroon Update 5)
}}}

!! [MacOS]
%%prettify 
{{{
system_profiler SPSoftwareDataType
}}} 
/%

Yields something like:
%%prettify 
{{{
Software:

    System Software Overview:

      System Version: macOS 10.13.1 (17B1003)
      Kernel Version: Darwin 17.2.0
      Boot Volume: org-disk
      Boot Mode: Normal
      Computer Name: jmac.willeke.com
      User Name: Jim Willeke (jim)
      Secure Virtual Memory: Enabled
      System Integrity Protection: Enabled
      Time since boot: 4:08
}}} 
/%

%%prettify 
{{{
defaults read loginwindow SystemVersionStampAsString
}}} 
/%

Yields something like:
%%prettify 
{{{
10.13.1
}}} 
/%

%%prettify 
{{{
sw_vers
}}} 
/%

Yields something like:
%%prettify 
{{{
ProductName:	Mac OS X
ProductVersion:	10.13.1
BuildVersion:	17B1003
}}} 
/%


!! More Information
There might be more information for this subject on one of the following:
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