$ answer=42 $ var=$(for i in $(seq $answer); do printf a; done) $ printf "%s\n\n" $var > file $ toybox grep -x $var file aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa Segmentation fault I haven't yet investigated the cause. 42 is the minimal value for the segfault to trigger. Possibly relevant: I'm using musl libc. Felix 1427568461.0