Helping user scripts use bin/sbang

[hartzell]

In a recent PR I pontificated about the importance of hardwiring the sbang line so that scripts use the interpreter with which they were built.

In the ongoing discussion about LD_LIBRARY_PATH I've learned that it's important to help "user-space" people use Spack-managed trees to build their own software.

Today I helped a "user-space" someone use the perl and cpanm from one of my test trees to install a CPAN-style distro, only to discover that the resulting sbang line in the distro's scripts was too long. (First we rediscovered spack/spack#4338, but that's fixed). My production trees have paths that squeak in under the line, phew.

Does anyone have any experience with helping "user-space" people use Spacks sbang-ification tools? Documentation about how they might use Spack sbanging code?

It seems as if one could write a fairly short script that accepted a directory name, imported the bits from lib/spack/spack/hooks/sbang.py and then called filter_shebangs_in_directory on it.

Perhaps I should write one and PR it to live in the bin directory alongside the spack command?

Is there a better solution?