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CSCI 1730 Final Exam Review Questions with
Correct Answers | Updated (100% Correct
Answers)
Kernel Answer: The core of an OS. Controls all hardware resources.
System Call Answer: Service points that allow programs to request
services from the kernel.
Shell Answer: A program that takes user commands from the
keyboard and executes those commands.
errno Answer: A special integer variable whose value represents a
type of error.
errno modification Answer: System calls, typically modify errno.
strerror(3) Answer: A function that returns a string which is an
informative representation of the meaning of the current value of
errno.
perror(3) Answer: A function that prints an informative string to
standard error.
File Descriptor Answer: A unique nonnegative integer associated
with each open file for a process.
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File Descriptor Assignment Answer: File descriptors are assigned by
the kernel. 0, 1, 2 are already open when a process starts.
Valid File Descriptors Answer: Nonnegative integers (0, 1, 2, 3, etc.)
Unbuffered I/O Answer: I/O operation that performs immediately by
invoking a system call.
Buffered I/O Answer: I/O operation that holds onto data in a
temporary storage (buffer).
fstat and stat struct Answer: Using fstat and the stat struct to
obtain file size, file permissions, and last modified timestamp.
I/O Redirection Answer: Redirecting standard input/output to a file.
dup vs. dup2 Answer: dup asks the kernel to assign a new file
descriptor, dup2 asks the kernel to use an existing file descriptor.
PID Answer: Process ID, a unique integer associated with each
process.
Special Processes Answer: PID 0 swapper/scheduler, PID 1 init, PID
2 pagedeamon.
Normal Process Termination Answer: Return from main, call exit(3),
_exit(2), or _Exit(2).
© 2025 All rights reserved
CSCI 1730 Final Exam Review Questions with
Correct Answers | Updated (100% Correct
Answers)
Kernel Answer: The core of an OS. Controls all hardware resources.
System Call Answer: Service points that allow programs to request
services from the kernel.
Shell Answer: A program that takes user commands from the
keyboard and executes those commands.
errno Answer: A special integer variable whose value represents a
type of error.
errno modification Answer: System calls, typically modify errno.
strerror(3) Answer: A function that returns a string which is an
informative representation of the meaning of the current value of
errno.
perror(3) Answer: A function that prints an informative string to
standard error.
File Descriptor Answer: A unique nonnegative integer associated
with each open file for a process.
© 2025 All rights reserved
, 2
File Descriptor Assignment Answer: File descriptors are assigned by
the kernel. 0, 1, 2 are already open when a process starts.
Valid File Descriptors Answer: Nonnegative integers (0, 1, 2, 3, etc.)
Unbuffered I/O Answer: I/O operation that performs immediately by
invoking a system call.
Buffered I/O Answer: I/O operation that holds onto data in a
temporary storage (buffer).
fstat and stat struct Answer: Using fstat and the stat struct to
obtain file size, file permissions, and last modified timestamp.
I/O Redirection Answer: Redirecting standard input/output to a file.
dup vs. dup2 Answer: dup asks the kernel to assign a new file
descriptor, dup2 asks the kernel to use an existing file descriptor.
PID Answer: Process ID, a unique integer associated with each
process.
Special Processes Answer: PID 0 swapper/scheduler, PID 1 init, PID
2 pagedeamon.
Normal Process Termination Answer: Return from main, call exit(3),
_exit(2), or _Exit(2).
© 2025 All rights reserved
