SC3056 – ShellCheck Wiki

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In POSIX sh, name matching prefixes are undefined.

(or "In dash, ... are not supported." when using dash)

Problematic code:

echo "${!ANDROID_*}"

Correct code:

The easiest solution is to switch to a shell that does support name matching prefixes, like bash:

echo "${!ANDROID_*}"

Alternatively, extract the data you want from env or set


Using ${!name*} to find all variable names with a given prefix is a bash and ksh extension that dash and POSIX sh does not support.


If you only intend to target shells 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.

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