Operating System MCQs

A signal notifies a process that an event has occurred and may trigger a registered handler.
Signals carry limited information compared with general message-passing mechanisms.

An ordinary pipe provides a byte-stream channel often used between related processes such as a parent and child.
It is not a memory-protection or storage-allocation structure.

A named pipe appears as a file-system object and can connect processes without a parent-child relationship.
An anonymous pipe is usually inherited through process creation.

A half-duplex pipe provides one directional data path at a time.
Two pipes may be used when independent two-way communication is required.

A message queue preserves message boundaries and decouples sending from immediate receiving.
The kernel manages the queue and its access rules.

A socket is a communication endpoint identified by addressing information and a transport protocol.
It supports local or networked process communication depending on the socket family.

Message passing transfers information as messages using operating-system communication primitives.
It is especially useful when processes do not share an address space.

Direct communication explicitly names the communication partner in send or receive operations.
This differs from indirect communication through a mailbox or port.

Indirect communication associates messages with a mailbox, port, or message queue.
Processes communicate by referring to that shared communication object.

A blocking send suspends the sender until the system or receiver has accepted the message as defined.
A nonblocking send returns control without waiting for that condition.

A nonblocking send lets the sender continue after submitting the message.
Delivery or reception may complete later depending on buffering and IPC semantics.

A blocking receive suspends the caller when no suitable message is available.
The process becomes runnable again after a matching message arrives.