Like you were told multiple times in the CB, the shell never see $dir — it sees its content — so it's useless to say `df $dir` without telling us what $dir contains.
It seems that it contains something that's either very long or something the shells expands into something very long.
In reply to Re: invoke shell with `` failed
by ikegami
in thread invoke shell with `` failed
by jiangliguo
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