Type the command, with no options, that lists the devices currently attached to the system's USB buses.
LPIC-1 Exam 101-500, objective 101. System architecture easy
Machine-checked — no person has signed for it. This question was read against the source cited below by an automated pass, which found no contradiction. That is a weaker claim than it sounds: the same kind of process wrote the question, so it can confirm its own mistake.
Treat it as a good draft rather than as settled fact, and read the source below before you rely on it. It is not used in mock exams here — only questions a person has signed for are.
How these questions are written — where each question comes from, what the verification ledger records, and what happens when one is found wrong.
Answer
Type the answer.
Accepted answers
lsusb/usr/bin/lsusb
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
lsusb prints one line per device with its bus and device number and its vendor:product ID. lsusb -t draws the bus topology as a tree, and lsusb -v prints the full descriptors. The PCI equivalent is lspci. Both read the information the kernel exposes under /sys and translate the numeric IDs into names using a local ID database.
Where this comes from
- Cited
- manual page lsusb(8)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 101 and space the ones you get wrong.
More questions on this objective
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- You are filing a hardware bug report and the maintainer asks for the raw PCI vendor and device ID numbers rather than the human-readable names lspci normally prints. Which lspci option produces the numeric IDs? machine-checked
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- A systemd-based machine fails during a normal boot because a service hangs. At the boot loader menu you want to edit the kernel command line for this one boot so the system comes up in single-user rescue mode instead. Which parameter do you append? machine-checked