SC3052 – ShellCheck Wiki

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In POSIX sh, arithmetic base conversion is undefined

Problematic code:

echo "Hex $1 is decimal $((16#$1))"

Correct code:

echo "Hex $1 is decimal $(echo "ibase=16; $1" | bc)"


Your script uses a shell feature not supported by the shebang. Either rewrite the script to be portable, or change the shebang to explicitly require a shell like Bash.

In this case, using radix specifiers in arithmetic contexts, such as $((16#DEADBEEF)) is not portable. bc ibase/obase can be used instead.



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