5.121 · exercise
Basic quiz: input and output
How printf, scanf and system calls move text in and out of a program: the addresses scanf needs, format specifiers, file descriptors, and the registers svc 0 reads.
0 of 6 correct
Multiple choice
A program reads one int with scanf into a .bss slot named age_n. What goes in x1 before bl scanf?
Multiple choice
Which file descriptor does a program write to when it sends a message to standard error?
Multiple choice
Before svc 0, which register holds the number that picks the system call?
Multiple choice
printf gets a 64-bit long in x1. Which conversion specifier prints all 64 bits?
Multiple choice
What does w0 hold when scanf("%d %d", ...) returns?
Multiple choice
A program calls printf, then sends a second line with the write system call, and its output goes to a file. Which line comes first in the file?