x86_64

View documentation for the original command

$ tldr setarch

Usually accessed internally via scripts checking the output of uname -m or arch. Not typically a direct command.

The `x86_64` command (often accessed indirectly) is used on Linux systems to determine if the underlying architecture is 64-bit x86 (also known as AMD64 or x64). It's often employed within scripts or build systems to conditionally execute code or configure software based on the architecture.

The command itself usually checks the output of commands like `uname -m` or `arch`. If the output contains strings like `x86_64`, `amd64`, or similar, it indicates a 64-bit x86 system. It's a simple but important check to ensure software is built and run correctly on the intended platform. The lack of a direct command with this name usually means that it's embedded within a script or alias, which contains a check for archictecture.

The `x86_64` command isn't a standard standalone utility. It's commonly a construct within shell scripts or build systems. Its behavior depends on the script's specific implementation.

The actual implementation within a script often involves using `uname -m` to retrieve the machine architecture, then using regular expressions or string comparisons to check if the output contains `x86_64`, `amd64`, or similar strings.
Example: if uname -m | grep -q x86_64; then echo '64-bit'; else echo '32-bit'; fi

While checking `uname -m` is common, other methods include examining the output of `arch` or `file /bin/ls` to glean information about the system's architecture.

The need to distinguish between 32-bit and 64-bit x86 architectures became increasingly important as 64-bit processors gained widespread adoption. Scripts began incorporating checks to ensure compatibility. The 'x86_64' identifier itself emerged as a common way to refer to the 64-bit architecture within these checks. Initially, the AMD64 architecture pushed for the wider adoption of 64 bit x86 processors, hence the name x86_64

uname(1), arch(1), file(1)