The following line is quite widespread in use, but not as portable as it could be: #!/bin/bash For increased portability, respect users' PATH environment

The following line is quite widespread in use, but not as portable as it could be: #!/bin/bash For increased portability, respect users' PATH environment variable using: #!/usr/bin/env bash Using #!/bin/bash could lead to subtle bugs on systems with more than one version of bash installed, or outright breakage on systems where bash isn't installed at /bin/bash. (OpenBSD is known to use /usr/local/bin/bash, for example.)