Yes, I realize now that I'm not doing my error checking correctly by using $! but my next question (read: obsession) is why do the perl C libraries set errno to "Bad file descriptor" whenever perl executes a shell command using backquotes that sends data to STDOUT?

Consider this:

perl -e '$res = `echo test`; print $!."\n";'

versus this:

perl -e '$res = `echo test>/dev/null`; print $!."\n";'

In the first example, $! is "Bad file descriptor". In the latter example, $! is empty. So whatever the answer is, it has something to do with whether or not the command has output. You can replace "echo test" with any shell command that produces STDOUT info.

In reply to Re^4: Using backquotes to echo results in "Bad file descriptor" by motionblurrr
in thread Using backquotes to echo results in "Bad file descriptor" by motionblurrr

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