[r6rs-discuss] [Formal] "#! /usr/bin/env" is not "portable." It's Unix-specific.

[Ben Goetter]

> R5.91RS codifies this practice: see section 3, page 10, second last 
> paragraph before 3.1, as well as 3.2.2.

This section of 5.91 seems to provide an escape.  Make #!/usr/bin/env 
indicate an "extension to the standard lexical syntax," meaning "skip 
the first line of this file."

That provides the necessary Unix trampoline magic for all the Unix 
users, including possible backslash brain damage for Unices that need a 
second line of command line parameters in their scheme_script, while 
leaving Unix shell script magic out of environments that don't need 
such.  Non-Unix environments would see #!/usr/bin/env as just another 
lexical extension not intended for their environment.