Hi Berny,
> > join -v 1 FILE1 FILE2
>
> Maybe awk?
>
> $ awk -v keyfile=file2 '
> BEGIN { while ((getline < keyfile) > 0) k[$1]=1 }
> !k[$1]
> ' file1
> or
>
> $ awk '
> keys { k[$1]=1; next }
> !k[$1]
> ' keys=1 file2 keys=0 file1
Wonderful! Thank you. Both solutions work fine with the 'awk' on Alpine Linux
(BusyBox v1.32.1).
> To be honest, I'm not sure whether the variable assignment on the command line
> or getline in a BEGIN block is more portable.
As Alpine Linux is the only platform that lacks 'join', awk portability is
not an issue (so far).
Bruno
