My brain doesn't cope well with

system("command") and die "Error message: $?";
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Although the above is perfectly valid - as system returns zero for success, unlike every other perl function I can think of - I'd much rather use:

system("command") == 0 or die "Error message: $?";
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Although I note that the examples in the perldoc use the latter approach, this is mostly a personal style point/grumble: feel free to ignore it.