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I know that it is possible to reverse "$@" using an array:

arr=( "$@" )

And using this answer, reverse the array.

But that requires a shell that has arrays.

It is also possible using tac:

set -- $( printf '%s\n' "$@" | tac )

But that breaks if the parameters have spaces or tab newlines (assuming the default value of $IFS) or contains wildcard characters (unless globbing is disabled beforehand) and removes empty elements, and requires the GNU tac command (using tail -r is slightly more portable outside of GNU systems but with some implementations fails on large input).

Is there a way to reverse shell positional arguments portably, without using an array, and that works even if arguments contain whitespaces or newlines or wildcards or are possibly empty?

I know that it is possible to reverse "$@" using an array:

arr=( "$@" )

And using this answer, reverse the array.

But that requires a shell that has arrays.

It is also possible using tac:

set -- $( printf '%s\n' "$@" | tac )

But that breaks if the parameters have spaces, tabs or newlines (assuming the default value of $IFS) or contain wildcard characters (unless globbing is disabled beforehand) and removes empty elements, and requires the GNU tac command (using tail -r is slightly more portable outside of GNU systems but with some implementations fails on large input).

Is there a way to reverse shell positional arguments portably, without using an array, and that works even if arguments contain whitespaces or newlines or wildcards or are possibly empty?

I know that it is possible to reverse "$@" using an array:

arr=( "$@" )

And using this answer, reverse the array.

But that requires a shell that has arrays.

It is also possible using tac:

set -- $( printf '%s\n' "$@" | tac )

But that breaks if the parameters have spaces or tab newlines (assuming the default value of $IFS) or contains wildcard characters (unless globbing is disabled beforehand) and removes empty elements.

Is there a way to reverse shell positional arguments portably, without using an array, and that works even if arguments contain spaces or newlines?

I know that it is possible to reverse "$@" using an array:

arr=( "$@" )

And using this answer, reverse the array.

But that requires a shell that has arrays.

It is also possible using tac:

set -- $( printf '%s\n' "$@" | tac )

But that breaks if the parameters have spaces or tab newlines (assuming the default value of $IFS) or contains wildcard characters (unless globbing is disabled beforehand) and removes empty elements, and requires the GNU tac command (using tail -r is slightly more portable outside of GNU systems but with some implementations fails on large input).

Is there a way to reverse shell positional arguments portably, without using an array, and that works even if arguments contain whitespaces or newlines or wildcards or are possibly empty?

I know that it is possible to reverse "$@" using an array:

arr=( "$@" )

And using this answer, reverse the array.

But that requires a shell that has arrays.

It is also possible using tac:

set -- $( printf '%s\n' "$@" | tac )

But that breaks if the parameters have spaces or newlines.

Is there a way to reverse shell positional arguments portably, without using an array, and that works even if arguments contain spaces or newlines?

I know that it is possible to reverse "$@" using an array:

arr=( "$@" )

And using this answer, reverse the array.

But that requires a shell that has arrays.

It is also possible using tac:

set -- $( printf '%s\n' "$@" | tac )

But that breaks if the parameters have spaces or tab newlines (assuming the default value of $IFS) or contains wildcard characters (unless globbing is disabled beforehand) and removes empty elements.

Is there a way to reverse shell positional arguments portably, without using an array, and that works even if arguments contain spaces or newlines?