How to find bash in a portable way

Question

When we write shell scripts we do this:

#!/bin/bash

But What if bash is in /usr/bin/? How can we find it in a portable way inside script? I did this, but it gives error:

#!which bash

Karlson · Accepted Answer · 2012-02-19 19:29:18Z

10

If bash is in the different location you can hash bang it as follows:

#!/usr/bin/env bash

Location for env is pretty standard across the variants.

answered Feb 19, 2012 at 19:29

Karlson

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7

A similar arabesque is useful for python scripts: #!/usr/bin/env python
– ncmathsadist
Feb 19, 2012 at 19:43
2

python, perl and all other scripting languages.
– Karlson
Feb 19, 2012 at 20:02
1

But this method does have some drawbacks; see this question and this answer. Most systems are going to install bash as /bin/bash (via a symlink if necessary) simply because so many scripts out there have #!/bin/bash.
– Keith Thompson
Feb 19, 2012 at 21:59
1

There are drawbacks to using either method but the fact that scripts out there use #!/bin/bash doesn't necessarily make them right.
– Karlson
Feb 20, 2012 at 0:57

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