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Comment by tlb | Hacker News Reader

Exec doesn't know about shell aliases. Only what's in the $PATH.

I liked the shell in MPW (Mac Programmer's Workshop, pre-NeXT) where common commands had both long names and short ones. You'd type the short ones at the prompt, but use the long, unambiguous ones in scripts.

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PowerShell has long commands and short aliases, but the aliases can still shadow executables, e.g. the `sc` alias for `Set-Content` shadows `sc.exe` for configuring services. And you only notice when you see no output and weird text files in the current working directory.

Networking crowd probably think it's obvious. Because of things like Cisco cli, or even Mikrotik. Or "ip" cli as well, I guess.

I never bothered to check what's the origin of that pattern.

Ive taken entire web farms offline due to an unexpected expansion of a command on a Cisco load balancer.

The command in question was:

    administer-all-port-shutdown

(Or something to that effect —it’s been many years now)

And so I went to log in via serial port (like I said, *many years ago so this device didn’t have SSH), didn’t get the prompt I was expecting. So typed the user name again:

    admin

And shortly afterwards all of our alarms started going off.

The worst part of the story is that this happened twice before I realised what I’d done!

I still maintain that the full command is a stupid name if it means a phrase as common as “admin” can turn your load balancer off. But I also learned a few valuable lessons about being more careful when running commands on Cisco gear.

Theoretically you could do this in Linux by calling /usr/bin/sl or whatever - but since various distros put binaries in different places, that would probably cause more problems than it could solve.

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