Appendix D: Compatibility Matrix#

# GNU file
$ file example.elf
example.elf: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked

# rmagic (current)
$ rmagic example.elf
example.elf: ELF 64-bit LSB executable

# rmagic (planned)
$ rmagic example.elf
example.elf: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked

# GNU file
$ file -i example.pdf
example.pdf: application/pdf; charset=binary

# rmagic (planned)
$ rmagic --mime-type example.pdf
example.pdf: application/pdf; charset=binary

# GNU file (recent versions)
$ file --json example.elf
[{"filename":"example.elf","mime-type":"application/x-pie-executable","mime-encoding":"binary","description":"ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked"}]

# rmagic (current)
$ rmagic --json example.elf
{
  "filename": "example.elf",
  "description": "ELF 64-bit LSB executable",
  "mime_type": "application/x-executable",
  "confidence": 1.0
}

# Old GNU file commands
file document.pdf
file -i document.pdf
file -b document.pdf
file -m custom.magic document.pdf

# New rmagic commands
rmagic document.pdf
rmagic --mime-type document.pdf # Planned
rmagic --brief document.pdf # Planned
rmagic --magic-file custom.magic document.pdf

#!/bin/bash
# Old script using GNU file
for f in *.bin; do
    type=$(file -b "$f")
    echo "File $f is: $type"
done

# New script using rmagic
for f in *.bin; do
    type=$(rmagic --brief "$f") # Planned
    echo "File $f is: $type"
done

// Old libmagic C code
#include <magic.h>

magic_t magic = magic_open(MAGIC_MIME_TYPE);
magic_load(magic, NULL);
const char* result = magic_file(magic, "file.bin");
printf("MIME type: %s\n", result);
magic_close(magic);

// New Rust code
use libmagic_rs::{MagicDatabase, EvaluationConfig};

let mut config = EvaluationConfig::default();
config.output_format = OutputFormat::MimeType; // Planned

let db = MagicDatabase::load_default()?;
let result = db.evaluate_file("file.bin")?;
println!("MIME type: {}", result.mime_type.unwrap_or_default());