CS degree from pitt.edu 1996 and C was not required. But a friend an I took it as an elective. We did not want to get out of school with CS degree and no C.
Wow. I started at a community college and they had two tracts for an Associate's in CS: Java and C++. Whichever you opted for, you took one class in C to get started; then 3 semesters of each language. You also had to take an assembler class or data structures and algorithms.
Transferred that to a UC and we definitely touched more ASM and C in the OS courses.
I went to Pitt from 1996-2000. In the first OS course, we did have some programming assignments in C, but it wasn't a good course and the assignments were mostly just using the Windows API. In the second OS course, the professor and his student had been working on an operating system simulator in Java (DORITOS, http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=736855...) and it was used to teach real-time systems programming without needing to get down to real hardware.
Turbo Pascal! I wrote this whole this to simulate file system inodes in pascal. We also did ADA and Smalltalk. But the main lang for everything back in my day was Pascal. Java was just starting when I was leaving.