# Generate a 32,767-character argument printf 'A%.0s' 1..32767 | xargs -0 echo Note: The above command requires xargs , which may not be available in stock Crosh. You have been warned. Did I miss a longer command? Do you know a hidden built-in that bypasses the limit? Let me know in the comments.
Why this number? It is a classic computing limit: (the maximum value of a signed 16-bit integer).
Crosh doesn't crash—it simply respects the POSIX ARG_MAX limit. Chrome OS’s little debug shell is more robust than it looks. longest command in crosh
Date: Draft Topic: Shell limits & buffer overflows in crosh
We found the wall. After narrowing it down, the longest successful command in Crosh is exactly: # Generate a 32,767-character argument printf 'A%
So, what happens when you try to break them? What is the you can type before Crosh gives up?
bash: /bin/echo: Argument list too long The echo command is a built-in in many shells, but in Crosh's restricted environment, echo often forks to /bin/echo . That hits ARG_MAX . Do you know a hidden built-in that bypasses the limit
For example, using a printf built-in (or just pressing Tab to trigger auto-complete), the buffer limit becomes —that is 2^17 - 1 .
echo AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA... (32,767 times) 0 Execution time: ~400ms (mostly rendering) Shell sanity after execution: Intact. Final Verdict The longest command in Crosh is 32,767 characters using an external binary, or 131,071 characters using a shell built-in.