Yes, PATH is the only environmental variable that influences how /usr/bin/env finds the executable.
But I was talking about tools like https://pypi.org/project/virtualenv/ where there's other things going on. That said, you are correct that there are some systems which install optional software to /usr/local/bin/, and I had forgotten about those. That said... I don't think there's any significant permissions problems involved in installing in /usr/bin on bsd systems. As I understand it, that's /usr/bin/env bash is a historical issue (and, thus, a backwards compatibility issue). Thanks, -- Raul On Fri, Mar 10, 2023 at 8:20 PM Elijah Stone <elro...@elronnd.net> wrote: > > > /usr/bin/env is the standard for developer systems where different > > configurations are managed through environmental variables. However, it's > > rather fragile for non-developers, as it requires properly conditioned > > environmental variables. > > This statement confuses me greatly. Can you elaborate? I think the only > environment variable which is relevant is PATH, and PATH will certainly > contain /usr/bin. So if PATH contains /usr/bin, and there is a > /usr/bin/ijconsole, then #!/usr/bin/env ijconsole will do the right thing. If > ijconsole is somewhere other than /usr/bin, and it is in PATH, then > #!/usr/bin/env ijconsole will pick it up, but #!/usr/bin/ijconsole will not. > So using /usr/bin/env is strictly less fragile. > > Using /usr/bin/env is standard for scripts. /usr/bin/ijconsole entails > _strictly_ more fuss, more fragility, and less portability. > > An example: on many BSD systems, bash does not come with the base system, but > is rather provided as a separate package, so it is placed in /usr/local/bin. > Some scripts developed on linux are distributed that use #!/bin/bash, and this > breaks on BSD systems because there is on bash in /bin; when those scripts use > #!/usr/bin/env bash instead, they work. > > On Fri, 10 Mar 2023, Raul Miller wrote: > > > > > /usr/bin/$name is the earlier standard for minimal fuss distribution. > > > > Given that most J users are going to be in some IDE, I don't see that > > the /usr/bin/env approach would provide significant benefit to the J > > community. Especially if we're considering people who would be baffled > > about what to do with #!/usr/bin/ijconsole > > > > Do you think I've overlooked something important here? > > > > Thanks, > > > > -- > > Raul > > > > On Fri, Mar 10, 2023 at 7:42 PM Elijah Stone <elro...@elronnd.net> wrote: > >> > >> Performance is irrelevant here--the difference in either case is miniscule. > >> > >> Using /usr/bin/env is standard practice in shebangs for finding binaries on > >> the path. In some systems, it is conventional to put binaries that did not > >> come with the system in /usr/local/bin, or in /opt; whereas, the existence > >> of > >> /usr/bin/env is mandated by posix. We should not presume any more than we > >> need to about the way a user's system will be organised. > >> > >> On Fri, 10 Mar 2023, Raul Miller wrote: > >> > >> > Yes, the name ijconsole (iverson j console) was adopted to work around > >> > java's jconsole being in $PATH on many systems. > >> > > >> > This would also be an issue with /usr/bin/env > >> > > >> > But I don't see any high priority problems with /usr/bin/ijconsole as > >> > a standard location. There will be some users who cannot install J > >> > there, but it should be simple enough for them to build a tool to > >> > patch incoming J scripts with the install location that they used. > >> > > >> > (And, /usr/bin/env is going to be considerably slower than a bit of > >> > undefined verb parsing and garbage collection within J.) > >> > > >> > -- > >> > Raul > >> > > >> > On Fri, Mar 10, 2023 at 6:51 PM Elijah Stone <elro...@elronnd.net> wrote: > >> >> > >> >> Fair enough. I think the obvious thing is #!/usr/bin/env jconsole. > >> >> But I > >> >> gather 'jconsole' is also the name of a java-related program, which > >> >> might be > >> >> why debian uses 'ijconsole' (and I think I have seen 'jc' > >> >> elsewhere--probably > >> >> for the same reason). I therefore propose: > >> >> > >> >> 1. Rename jconsole to something which doesn't collide with anything > >> >> heretofore > >> >> notable > >> >> > >> >> 2. Use #!/usr/bin/env that-something > >> >> > >> >> On Fri, 10 Mar 2023, Raul Miller wrote: > >> >> > >> >> > Perhaps, but I think it would be more useful to have a portable, > >> >> > agreed on path for systems which support the #! convention. > >> >> > > >> >> > That's required for J scripts to be distributable. > >> >> > > >> >> > Thanks, > >> >> > > >> >> > -- > >> >> > Raul > >> >> > > >> >> > On Fri, Mar 10, 2023 at 12:04 AM Elijah Stone <elro...@elronnd.net> > >> >> > wrote: > >> >> >> > >> >> >> Perhaps it's simply time to tell the interpreter to start ignoring > >> >> >> the first > >> >> >> line of a script if it starts with #!... > >> >> >> > >> >> >> On Thu, 9 Mar 2023, Raul Miller wrote: > >> >> >> > >> >> >> > The recent change in directory naming from j903 to j9.4 introduces > >> >> >> > an > >> >> >> > interesting issue for shell scripts on unix-like systems. > >> >> >> > > >> >> >> > In J shell scripts, this works: > >> >> >> > > >> >> >> > #!/home/username/j903/bin/jconsole > >> >> >> > > >> >> >> > However, this fails with a spelling error: > >> >> >> > > >> >> >> > #!/home/username/j9.4/bin/jconsole > >> >> >> > > >> >> >> > Or, on OSX, the shebang line is different, but the spelling error > >> >> >> > remains: > >> >> >> > > >> >> >> > #!/Applications/j9.4/bin/jconsole > >> >> >> > > >> >> >> > That said, there's some other issues here, related to portability. > >> >> >> > One > >> >> >> > of which is that (as a general rule) a home directory is personal > >> >> >> > rather than portable. Another is that there's official java > >> >> >> > jconsole > >> >> >> > which does not understand J. > >> >> >> > > >> >> >> > But, also, for a long time now, Debian based distributions have > >> >> >> > been > >> >> >> > distributing j with /usr/bin/ijconsole as a symbolic link to the > >> >> >> > current installed location for J. (Here, the 'i' in ijconsole > >> >> >> > stands > >> >> >> > for Iverson.) > >> >> >> > > >> >> >> > So I think that now would be a good time to adopt that as > >> >> >> > "documented > >> >> >> > standard practice" for j shell scripts. > >> >> >> > > >> >> >> > FYI, > >> >> >> > > >> >> >> > -- > >> >> >> > Raul > >> >> >> > ---------------------------------------------------------------------- > >> >> >> > For information about J forums see > >> >> >> > http://www.jsoftware.com/forums.htm > >> >> >> ---------------------------------------------------------------------- > >> >> >> For information about J forums see > >> >> >> http://www.jsoftware.com/forums.htm > >> >> > ---------------------------------------------------------------------- > >> >> > For information about J forums see http://www.jsoftware.com/forums.htm > >> >> ---------------------------------------------------------------------- > >> >> For information about J forums see http://www.jsoftware.com/forums.htm > >> > ---------------------------------------------------------------------- > >> > For information about J forums see http://www.jsoftware.com/forums.htm > >> ---------------------------------------------------------------------- > >> For information about J forums see http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
