SC3037 – ShellCheck Wiki

Sitemap

In POSIX sh, echo flags are undefined.

Problematic code:

#!/bin/sh
echo -ne 'Foo:\tBar'

Correct code:

Rewrite in terms of the more robust and standardized printf:

#!/bin/sh
printf 'Foo:\tBar'

Rationale:

echo has historically behaved differently on different systems. Use printf instead to ensure compatibility between shells.

Exceptions:

If you only intend to target systems that supports this feature, you can change the shebang to a shell that guarantees support, or ignore this warning.

You can use # shellcheck disable=SC3000-SC4000 to ignore all such compatibility warnings.

Related resources:

• Help by adding links to BashFAQ, StackOverflow, man pages, POSIX, etc!

ShellCheck is a static analysis tool for shell scripts. This page is part of its documentation.