jsocketpp::ReadExactOptions Struct Reference

Policy for enforcing an exact-byte receive on a single UDP datagram. More...

#include <DatagramSocket.hpp>

Collaboration diagram for jsocketpp::ReadExactOptions:

Public Attributes
DatagramReadOptions	base {}
	Base receive options for controlling preflight behavior, system flags, and side effects.
bool	requireExact = true
	Controls whether the datagram size must match exactly.
bool	padIfSmaller = false
	Controls zero-padding behavior for undersized datagrams.
bool	errorOnTruncate = true
	Controls error handling for oversized datagrams.
bool	autoResizeDynamic = true
	Controls automatic resizing of dynamic containers.

Detailed Description

Policy for enforcing an exact-byte receive on a single UDP datagram.

This structure defines the policy for reading a UDP datagram that must match a specific size requirement. It provides fine-grained control over the handling of datagrams that are larger or smaller than the expected size, including padding behavior and error handling.

Key Features

• Enforces exact datagram size matching
• Controls zero-padding behavior for undersized datagrams
• Manages truncation vs error behavior for oversized datagrams
• Supports automatic buffer resizing for dynamic containers

See also

DatagramSocket::readExact()

DatagramSocket::readIntoExact()

Since

1.0

Member Data Documentation

autoResizeDynamic

bool jsocketpp::ReadExactOptions::autoResizeDynamic = true

Controls automatic resizing of dynamic containers.

When true and receiving into a dynamic container (e.g., std::string, std::vector), the container will be automatically resized to the exact size before the receive operation.

This ensures efficient memory use but may trigger reallocation.

Note

Has no effect on fixed-size containers or raw buffers.

base

DatagramReadOptions jsocketpp::ReadExactOptions::base {}

Base receive options for controlling preflight behavior, system flags, and side effects.

This field inherits the core receive options from DatagramReadOptions, including:

• Datagram sizing mode (DatagramReceiveMode)
• Buffer growth/shrink policies
• Additional receive flags (e.g., MSG_PEEK)
• Remote peer tracking and address resolution

See also

DatagramReadOptions

errorOnTruncate

bool jsocketpp::ReadExactOptions::errorOnTruncate = true

Controls error handling for oversized datagrams.

When true, receiving a datagram larger than the requested size will throw a SocketException. When false, the datagram is silently truncated to the requested size.

Note

Only meaningful when requireExact is false.

padIfSmaller

bool jsocketpp::ReadExactOptions::padIfSmaller = false

Controls zero-padding behavior for undersized datagrams.

When true and the received datagram is smaller than the requested size:

• For raw buffers: fill remaining bytes with zeros
• For fixed-size containers: zero-initialize unused space
• For dynamic containers: no effect (container is sized to actual data)

Note

Only meaningful when requireExact is false.

requireExact

bool jsocketpp::ReadExactOptions::requireExact = true

Controls whether the datagram size must match exactly.

When true, the datagram's payload size must match the requested size exactly; otherwise, a SocketException is thrown. This enforces strict size matching for protocols that require fixed-size messages.

Note

This is independent of padIfSmaller and errorOnTruncate, which control how size mismatches are handled when this is false.

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The documentation for this struct was generated from the following file:

• include/jsocketpp/DatagramSocket.hpp