arch

Display the system's architecture

$ arch

arch [OPTION]...

--help
    Displays a help message and exits.


--version
    Outputs version information and exits.

The arch command is a straightforward utility used to display the machine architecture (CPU type) of the current system. It typically outputs a string identifying the hardware platform, such as x86_64 for modern 64-bit Intel/AMD systems, aarch64 for ARM 64-bit, or i686 for older 32-bit systems. This command is often employed in shell scripts to conditionally execute code based on the underlying architecture, ensuring compatibility or optimizing performance for specific platforms. It provides a quick and concise way to query this fundamental system attribute, acting as a convenient shorthand for uname -m. Part of the GNU Core Utilities, arch is a widely available and stable command across most Linux distributions.

The arch command primarily reports the architecture of the kernel rather than the specific user-space environment, which might be relevant in chroot or containerized setups.
Its output can be less specific than uname -m in some cases, providing a generic identifier (e.g., i686) even for systems capable of more advanced instruction sets.
It's essentially a symbolic link or a simple wrapper for uname -m on many modern systems, so direct use of uname -m offers more control and consistency.

arch returns 0 upon successful execution and a non-zero value if an error occurs (e.g., invalid option).

The arch command is a legacy utility that has been a part of Unix-like systems for a long time, now included in the GNU Core Utilities. Its functionality is minimal and highly stable, having served its purpose of providing a quick architecture string since early Linux development. It predates many modern system information tools but remains a widely used, simple command due to its universal availability and straightforward output.

uname(1), hostname(1), lsb_release(1)