Instead of writing a multiline if/then/else/fi construct you can do that by one line
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This will perform one of two blocks of code, depending on the condition of the first. Essentially is a bash terniary operator. To tell if a machine is up:
ping -c1 machine { echo succes;} || { echo failed; }Because of the bash { } block operators, you can have multiple commandsping -c1 machine && { echo success;log-timestamp.sh }|| { echo failed; email-admin.sh; }Tips: Remember, the { } operators are treated by bash as a reserved word: as such, they need a space on either side. If you have a command that can fail at the end of the true block, consider ending said block with 'false' to prevent accidental execution Show Sample Output23true && { echo success;} || { echo failed; }
What do you think?
Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?
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[[ true ]] && false || echo "Not exactly the same."if [[ test_condition ]]; then do_stuff_here; else do_other_stuff_here; fione advantage of using the actual if-statement is that you can add things in either clause without needing to use a set of braces. If you wanted to do it with braces, though, you could do:[[ test_condition ]] && { true_stuff_1; true_stuff_2; } || { false_stuff_1; false_stuff_2; }