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21.4 uname: Print system information

uname prints information about the machine and operating system it is run on. If no options are given, uname acts as if the -s option were given. Synopsis:

     uname [option]...

If multiple options or -a are given, the selected information is printed in this order:

     kernel-name nodename kernel-release kernel-version
     machine processor hardware-platform operating-system

The information may contain internal spaces, so such output cannot be parsed reliably. In the following example, release is ‘2.2.18ss.e820-bda652a #4 SMP Tue Jun 5 11:24:08 PDT 2001’:

     uname -a
     ⇒ Linux dumdum 2.2.18 #4 SMP Tue Jun 5 11:24:08 PDT 2001 i686 unknown unknown GNU/Linux

The program accepts the following options. Also see Common options.

-a
--all
Print all of the below information, except omit the processor type and the hardware platform name if they are unknown.
-i
--hardware-platform
Print the hardware platform name (sometimes called the hardware implementation). Print ‘unknown’ if the kernel does not make this information easily available, as is the case with Linux kernels.
-m
--machine
Print the machine hardware name (sometimes called the hardware class or hardware type).
-n
--nodename
Print the network node hostname.
-p
--processor
Print the processor type (sometimes called the instruction set architecture or ISA). Print ‘unknown’ if the kernel does not make this information easily available, as is the case with Linux kernels.
-o
--operating-system
Print the name of the operating system.
-r
--kernel-release
Print the kernel release.
-s
--kernel-name
Print the kernel name. POSIX 1003.1-2001 (see Standards conformance) calls this “the implementation of the operating system”, because the POSIX specification itself has no notion of “kernel”. The kernel name might be the same as the operating system name printed by the -o or --operating-system option, but it might differ. Some operating systems (e.g., FreeBSD, HP-UX) have the same name as their underlying kernels; others (e.g., GNU/Linux, Solaris) do not.
-v
--kernel-version
Print the kernel version.

An exit status of zero indicates success, and a nonzero value indicates failure.