The var $! refers to the C library errno global variable. It is set in many places in the runtime system. errno is not explicitly reset by any library function.

You should only check $! if you know there is an error. (Such as after a failed open.) In fact, perlvar specifically states that it is meaningless if an error has not occurred.

In this case, you probably want $? which contains the error generated by the backticks operator.

G. Wade

In reply to Re: Using backquotes to echo results in "Bad file descriptor" by gwadej
in thread Using backquotes to echo results in "Bad file descriptor" by motionblurrr

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