fileunixnullcutnul

How to 'cut' on null?


Unix 'file' command has a -0 option to output a null character after a filename. This is supposedly good for using with 'cut'.

From man file:

-0, --print0
         Output a null character ‘\0’ after the end of the filename. Nice
         to cut(1) the output. This does not affect the separator which is
         still printed.

(Note, on my Linux, the '-F' separator is NOT printed - which makes more sense to me.)

How can you use 'cut' to extract a filename from output of 'file'?

This is what I want to do:

find . "*" -type f | file -n0iNf - | cut -d<null> -f1

where <null> is the NUL character.

Well, that is what I am trying to do, what I want to do is get all file names from a directory tree that have a particular MIME type. I use a grep (not shown).

I want to handle all legal file names and not get stuck on file names with colons, for example, in their name. Hence, NUL would be excellent.

I guess non-cut solutions are fine too, but I hate to give up on a simple idea.


Solution

  • Just specify an empty delimiter:

    cut -d '' -f1
    

    Notes: