gistfile1.txt

FROM ubuntu
ENV foo=bar
RUN asdasd || echo hi
RUN 123



$ docker build . > out 2> err
$ cat out
Sending build context to Docker daemon 40.09 MB
Step 1 : FROM ubuntu
 ---> a5a467fddcb8
Step 2 : ENV foo bar
 ---> Using cache
 ---> ab644e134785
Step 3 : RUN asdasd || echo hi
 ---> Running in 5d0ea420d9c7
/bin/sh: 1: asdasd: not found
hi
 ---> 9e92fb78f90c
Removing intermediate container 5d0ea420d9c7
Step 4 : RUN 123
 ---> Running in acef3ff96757
/bin/sh: 1: 123: not found

$ cat err
The command '/bin/sh -c 123' returned a non-zero code: 127