That’s true, but even single variables , if they’re set by rc, will have a null termination
On Wed, Jun 4, 2025 at 15:04 Romano <[email protected]> wrote: > IIRC correctly, if you store a list to an environment variable, then the > elements are NUL separated. I think I saw that a year ago when poking > around the rc source. For example: > cpu% a=(ab c d) > cpu% xd /env/a > ... > > On Wed, Jun 4, 2025, at 9:26 AM, ron minnich wrote: > > anyway, I found it, when you do this in rc: > x=y > rc writes a trailing null. > > Not sure that's needed, but it's what it does. I'm going to strip trailing > nulls in the cpu command. > > On Wed, Jun 4, 2025 at 7:55 AM ron minnich <[email protected]> wrote: > > I'll be submitting a PR to fix it, we'll see how that goes, because the > code, as written, doesn't even give you some idea how many variables had > the problem. > > I don't see that exposing those names is that big a deal, but we'll see. > > > On Tue, Jun 3, 2025 at 5:15 PM Daniel Maslowski via 9fans <[email protected]> > wrote: > > The author of that error message might have chosen to not expose/disclose > the information. > > Anyway, interesting - would be really nice to see both systems integrate > seamlessly! > I have a good collection of hardware by now that would really like to see > this. > > On Wed, Jun 4, 2025 at 1:57 AM ron minnich <[email protected]> wrote: > > well, here's a fun one. > > I've got my golang cpu command working on plan 9. So I'm working to have > my plan 9 cpu connect to a linux vmx guest running my golang cpud. > > The linux kernel has the initramfs builtin, so ... one file for vmx to > worry about, and 0 disk images. > > side note: qemu was choking on this kernel somehow, but vmx ran it just > fine. I like vmx much more than qemu at this point. I prefer to test these > linux kernels on vmx now. > > The goal is to have a linux appliance process, where it is easy to (e.g.) > run python3. So the only thing embedded in the linux kernel is u-root > programs and a cpud. You should be able to cd to the root of a linux file > system, and say > linux usr/bin/python3 > where linux is a wrapper for vmx, and have it work. We had this on akaros. > It's handy. > > The only big problem will be the plethora of symlinks in linux images, but > I have a workaround for that, so we'll see. > > Anyway, plan 9 cpu was connecting to linux cpud, mounts were happening, > and so on, then I got this on the cpud side: > "exec: environment variable contains NUL" > and the cpud exec failed. > WTH? Well, it turns out, it's this in src/os/exec/exec.go. > > // Reject NUL in environment variables to prevent security > issues (#56284); > // except on Plan 9, which uses NUL as > os.PathListSeparator (#56544). > > The problem is, this doesn't work if you are communicating plan 9 > environment variables to Linux, and that's what we're doing. You kind of > have to for cpu. I will guess I'm the first person to see this ... kind of > funny. Working on it. > > I'm a bit annoyed that whoever wrote the test and error did this: > err = errors.New("exec: environment variable contains NUL" > instead of this: > err = fmt.Errorf"%q:exec: environment variable contains NUL", kv) > since it's always kind of nice to produce useful error messages :-) > but at least I got something! > > btw, my talk, the paper, and the code for vmthreads is mirrored to > github.com/rminnich/vmproc. > > > > > *9fans <https://9fans.topicbox.com/latest>* / 9fans / see discussions > <https://9fans.topicbox.com/groups/9fans> + participants > <https://9fans.topicbox.com/groups/9fans/members> + delivery options > <https://9fans.topicbox.com/groups/9fans/subscription> Permalink > <https://9fans.topicbox.com/groups/9fans/T9b0ff93502ee4130-M9f93c78b692bce940fbd2461> > ------------------------------------------ 9fans: 9fans Permalink: https://9fans.topicbox.com/groups/9fans/T9b0ff93502ee4130-M0a64be9fd0ed2b7248ae9bca Delivery options: https://9fans.topicbox.com/groups/9fans/subscription
