iyzs...@member.fsf.org (宋文武) skribis: > Someone (sorry, I forget who) mentioned in #guix that we can use > binfmt_misc to handle the shebang. > > I tried coding it in C, and it seems to working fine. > Here it is: <https://github.com/iyzsong/duang>. > > Try it with care: > $ sudo mount -t binfmt_misc binfmt_misc /proc/sys/fs/binfmt_misc > $ git clone https://github.com/iyzsong/duang.git > $ cd duang > $ make > $ sudo make install > $ sudo make register > > This will install the handler into `/libexec/@', and register it in > `/proc/sys/fs/binfmt_misc/duang'. With it activated, intepreter in > the shebang doesn't need to be absolute path, and can handle multiple > arguments, eg: `#!emacs -Q --script'. And when the interpreter in > absolute path is not exist, it will fallback to be searched in the PATH, > so `#!/usr/bin/perl -w' equals to `#!perl -w'. On GuixSD, this means > if we remove the `/bin/sh' symlink, the sh-scripts will fallbacked to > use `sh' in PATH, so we can remove /bin. > > I dunno if it's a good idea though :-)
Nice hack! :-) The downside is that it requires scripts to use this feature, and requires users to have Duang installed and registered. I think what would be nice to handle the use case that Andy raised is a binfmt_misc handler that simply handles /usr/bin/env (and possibly /bin/sh), and to add an ‘operating-system’ knob to enable it. That way, third-party scripts would work automagically. Thanks, Ludo’.
