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brr64

Have you ever looked for base64 encoded content in multiple, huge files? You dont want to decode, but just find the text? brr64 generates a regular expression which contains all possibilities of the total base64 encoded content. No false-positives or true-negatives. This allows you to search in a flat-file manner, without decoding base64 at all.

Input

because after every base64 character, there might be a newline.
helps you understanding how brr64 works. Leave this off when searching for something.
Works with Unicode, newline, carriage return and basically everything. Something does not work? Open an issue.

Output

Please note that the provided grep command, prints the byte-offset not the line number. The generated regular expression consists of three candidates. When given input is empty, only one candidate exists: the empty candidate. brr64 will print three same candidates for the empty case(s): "(||)".