How to detect a file type on busybox

Question

Busybox does not include the traditional linux "file" commad. Is there any alternative way to detect whether a file is binary or ascii? Thanks

Answer 1

You can try using grep. This thread contains some variants of using grep command: https://stackoverflow.com/a/30133802/3694234. For me, this command works fine.

$ grep -P "[^\x00-\x7F]" filename && echo Binary || echo Text

You can use this in a bash script

#!/bin/bash

type=$(grep -P "[^\x00-\x7F]" $1 > /dev/null && echo Binary || echo Text)

echo "File type: ${type}"

Sample output

$ ./getFileType.sh test.c 
File type: Text
$ ./getFileType.sh test
File type: Binary