I think you want to replace "shell" with "kernel". I suppose it could be in libc, but I'm certain it's not in /bin/sh, except for cygwin.

No, sorry, shells have to have a fallback mechanism if your O/S claims POSIX compatibility. See Re^2: Shebang behavior with perl. It's not in libc. But yes, usually the kernel extracts the interpreter and the argument (note: singular) from the shebang line.

Alexander

The linked page in your other response only has this reference to the shebang line:

The shell reads its input from a file (see sh), from the -c option or from the system() and popen() functions defined in the System Interfaces volume of POSIX.1-2017. If the first line of a file of shell commands starts with the characters "#!", the results are unspecified.

The last I checked, /bin/sh on Solaris wasn't even POSIX compliant, so you can't count on that. So, to go back to the OP, I would say for maximum portability to write a bourne shell (/bin/sh) wrapper to run it, or give this snippet from perlrun a try to avoid a wrapper:

#!/bin/sh
#! -*-perl-*-
eval 'exec perl -x -wS $0 ${1+"$@"}'
    if 0;
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