The system utility fsck is a tool for checking the consistency of a file system in Unix and Unix-like operating systems, such as Linux, macOS, and FreeBSD. The equivalent programs on MS-DOS and Microsoft Windows are CHKDSK, SFC, and SCANDISK.
https://en.m.wikipedia.org/wiki/Fsck
I think it’s kind of like saying “check yourself”
Didn’t they quickly stop this after it became the Nazis favorite thing?