Linux · Files, Directories & Links

In ls -l output, what is the single number sitting between the permission string and the owner name — and what does an unexpectedly high value there hint at?

Answer locked. Get the free KnowCard app to reveal it — plus spaced-repetition review so it actually sticks.

This is one card from the KnowCard library — thousands more across SAP, Linux, Python and more. In the app you get the answer, AI explanations, and cards that come back right before you would forget them. Free to start on iOS, Android or the web.

More in Files, Directories & Links

You add a second SATA SSD, then plug in an NVMe drive. Following the standard naming scheme, what device files does the kernel assign to each?

On an MBR-partitioned disk you create partitions but there's a gap in the numbering — the first data partition after the primary ones is /dev/sda5, not /dev/sda3. Why?

For a SATA disk the third partition is /dev/sda3, but for an NVMe SSD the first partition is /dev/nvme0n1p1. What naming rule differs?

From the Linux kernel's point of view, which two characters can never appear inside a file name — and what does that imply about names like a colon, backslash, or newline?

Two files are named report.txt and Report.txt in the same directory. On Linux, are these the same file or two different files?

A user swears their config file is gone because ls shows an empty home directory, but the file is still there. What's the most likely explanation?

Start learning today

Free to start — download the app or use it in your browser.