#!/bin/sh Vs #!/bin/bash For Maximum Portability
Answer : Solution 1: There are roughly four levels of portability for shell scripts (as far as the shebang line is concerned): Most portable: use a #!/bin/sh shebang and use only the basic shell syntax specified in the POSIX standard. This should work on pretty much any POSIX/unix/linux system. (Well, except Solaris 10 and earlier which had the real legacy Bourne shell, predating POSIX so non compliant, as /bin/sh .) Second most portable: use a #!/bin/bash (or #!/usr/bin/env bash ) shebang line, and stick to bash v3 features. This'll work on any system that has bash (in the expected location). Third most portable: use a #!/bin/bash (or #!/usr/bin/env bash ) shebang line, and use bash v4 features. This'll fail on any system that has bash v3 (e.g. macOS, which has to use it for licensing reasons). Least portable: use a #!/bin/sh shebang and use bash extensions to the POSIX shell syntax. This will fail on any system that has something other than bash for /bin/sh (su...