How to use the command 'grub-file' (with examples)

The ‘grub-file’ command is used to check whether a file is of a specific bootable image type. This can be useful when troubleshooting issues related to boot loaders or kernel images. The command supports various options to check for different types of images.

Use case 1: Check if a file is an ARM EFI image

Code:

grub-file --is-arm-efi path/to/file

Motivation: ARM EFI images are used for booting ARM-based systems that use the Extensible Firmware Interface (EFI). By using this command, you can quickly determine if a file is an ARM EFI image, which can be helpful in diagnosing boot-related problems on ARM devices.

Explanation: The ‘–is-arm-efi’ option is used to check if the given file is an ARM EFI image. The ‘path/to/file’ should be replaced with the actual file path you want to check.

Example output:

path/to/file: UEFI image ARM

Use case 2: Check if a file is an i386 EFI image

Code:

grub-file --is-i386-efi path/to/file

Motivation: i386 EFI images are used for booting systems with 32-bit Intel processors using EFI. By checking if a file is an i386 EFI image, you can determine if a boot-related issue is caused by the EFI image compatibility on your system.

Explanation: The ‘–is-i386-efi’ option is used to check if the given file is an i386 EFI image. Replace ‘path/to/file’ with the actual file path you want to check.

Example output:

path/to/file: UEFI image i386

Use case 3: Check if a file is an x86_64 EFI image

Code:

grub-file --is-x86_64-efi path/to/file

Motivation: x86_64 EFI images are used for booting systems with 64-bit Intel processors using EFI. By checking if a file is an x86_64 EFI image, you can verify the compatibility of the EFI image with your system and troubleshoot any boot-related issues.

Explanation: The ‘–is-x86_64-efi’ option is used to check if the given file is an x86_64 EFI image. Replace ‘path/to/file’ with the actual file path you want to check.

Example output:

path/to/file: UEFI image x86_64

Use case 4: Check if a file is an ARM image (Linux kernel)

Code:

grub-file --is-arm-linux path/to/file

Motivation: ARM images are Linux kernel images specifically built for ARM-based systems. Verifying if a file is an ARM image can help in troubleshooting issues related to the kernel compatibility on ARM devices.

Explanation: The ‘–is-arm-linux’ option is used to check if the given file is an ARM image (Linux kernel). Replace ‘path/to/file’ with the actual file path you want to check.

Example output:

path/to/file: GRUB ARM Linux boot executable

Use case 5: Check if a file is an x86 image (Linux kernel)

Code:

grub-file --is-x86-linux path/to/file

Motivation: x86 images are Linux kernel images specifically built for systems with 32-bit Intel processors. Verifying if a file is an x86 image can help in diagnosing kernel-related issues on systems using Intel processors.

Explanation: The ‘–is-x86-linux’ option is used to check if the given file is an x86 image (Linux kernel). Replace ‘path/to/file’ with the actual file path you want to check.

Example output:

path/to/file: Legacy i386 Linux kernel executable

Use case 6: Check if a file is an x86_64 XNU image (Mac OS X kernel)

Code:

grub-file --is-x86_64-xnu path/to/file

Motivation: x86_64 XNU images are kernel images specific to Mac OS X. By checking if a file is an x86_64 XNU image, you can determine if a boot-related issue is related to the Mac OS X kernel.

Explanation: The ‘–is-x86_64-xnu’ option is used to check if the given file is an x86_64 XNU image (Mac OS X kernel). Replace ‘path/to/file’ with the actual file path you want to check.

Example output:

path/to/file: x86_64 XNU boot executable

Conclusion:

The ‘grub-file’ command is a useful tool for checking the bootable image type of a file. By using the appropriate option, you can easily determine if a file is an EFI image or a specific architecture-specific kernel image. This can be helpful in debugging boot-related issues and ensuring the compatibility of boot loaders and kernels with the target system architecture.