But my main reason is that most scripts break when you call them with filenames that contain spaces. And they break spectacularly.
You have to write the crappy sh script once but then you get simple, easy usage every time. (If you're revising the script frequently enough that sh/bash are the bottleneck, then what you have is a dev project and not a script, use a programming language).
Three factors conspire to make a bug:
1. Someone decides to use a space
2. We use Python
3. macOS
#!/usr/bin/env python3
Since we use Python virtualenvs,
#!/home/bob/src/repo/.venv/bin/python3
#!/home/bob/src/repo with a space/.venv/bin/python3
As I also discovered when I discovered this, the Python tooling checks for this! It will instead emit a polyglot!
#!/bin/bash
# <what follows in a bash/python polyglot>
# the bash will find the right Python interpreter, and then re-exec this
# script using that interpreter. The Python will skip the bash portion,
# b/c of cleverness in the polyglot.
Took me forever to figure out what was going on. So yeah … spaces in paths. Can't recommend them. Stuff breaks, and it breaks in weird and hard to debug ways.
I suppose it would also need env to be able to handle paths that have spaces in them.
My practical view is to avoid spaces in directories and filenames, but to write scripts that handle them just fine (using BASH - I'm guilty of using it when more sane people would be using a proper language).
My ideological view is that unix/POSIX filenames are allowed to use any character except for NULL, so tools should respect that and handle files/dirs correctly.
I suppose for your usage, it'd be better to put the virtualenv directory into your path and then use #!/usr/bin/env python
I'd give this a try, works with any language:
#!/usr/bin/env -S "/path/with spaces/my interpreter" --flag1 --flag2
#!/bin/sh
exec "/path/with spaces/my interpreter" "$0" "$@"
Python
#!/bin/sh
""":"
exec "/path/with spaces/my interpreter" "$0" "$@"
":"""
# Python starts here
print("ok")
#!/bin/sh
exec "/path/with spaces/ruby" -x "$0" "$@"
#!ruby
puts "ok"
#!/bin/sh
/* 2>/dev/null
exec "/path/with spaces/node" "$0" "$@"
*/
console.log("ok");
#!/bin/sh
exec "/path/with spaces/perl" -x "$0" "$@"
#!perl
print "ok\n";
#!/bin/sh
#|
exec "/path/with spaces/sbcl" --script "$0" "$@"
|#
(format t "ok~%")
#!/bin/sh
#if 0
exec "/path/with spaces/tcc" -run "$0" "$@"
#endif
#include <stdio.h>
int main(int argc, char **argv)
{
puts("ok");
return 0;
}
#!/bin/sh
#|
exec "/path/with spaces/racket" "$0" "$@"
|#
#lang racket
(displayln "ok")
#!/bin/sh
#if 0
exec "/path/with spaces/runghc" -cpp "$0" "$@"
#endif
main :: IO ()
main = putStrLn "ok"
#!/usr/bin/env bash
exec "/path/with spaces/ocaml" -no-version /dev/fd/3 "$@" 3< <(tail -n +3 "$0")
print_endline "ok";;