Did you read error indicators? Essentially (as gwadej and toolic as also pointed out) you are not checking the error code you think you are. $! is set by the perl C libraries, not by external system calls, and its value is essentially meaningless unless a Perl library call (like open) just failed. On the other hand $? is set to the return value of the invoked system call, and as such is what you need to check in the case of backticks (or system).

In reply to Re^3: Using backquotes to echo results in "Bad file descriptor" by kennethk
in thread Using backquotes to echo results in "Bad file descriptor" by motionblurrr

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