SC2112

`function` keyword is non-standard. Delete it.

#!/bin/sh
function hello() {
  echo "Hello World"
}

#!/bin/sh
hello() {
  echo "Hello World"
}

The function keyword is a feature of Bash and Ksh, so code that uses it may be intended to be a Bash or Ksh script instead:

#!/bin/bash
function hello() {
  echo "Hello World"
}

function is a non-standard keyword that can be used to declare functions in Bash and Ksh.

In POSIX sh and dash, a function is instead declared without the function keyword as in the correct example.

None.

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