System

Reset reason, restart, shutdown handlers, and heap information. More...

Namespaces
namespace	idfxx

Enumerations
enum class	idfxx::reset_reason : int {   idfxx::reset_reason::unknown = 0 ,   idfxx::reset_reason::power_on = 1 ,   idfxx::reset_reason::external = 2 ,   idfxx::reset_reason::software = 3 ,   idfxx::reset_reason::panic = 4 ,   idfxx::reset_reason::interrupt_watchdog = 5 ,   idfxx::reset_reason::task_watchdog = 6 ,   idfxx::reset_reason::watchdog = 7 ,   idfxx::reset_reason::deep_sleep = 8 ,   idfxx::reset_reason::brownout = 9 ,   idfxx::reset_reason::sdio = 10 ,   idfxx::reset_reason::usb = 11 ,   idfxx::reset_reason::jtag = 12 ,   idfxx::reset_reason::efuse = 13 ,   idfxx::reset_reason::power_glitch = 14 ,   idfxx::reset_reason::cpu_lockup = 15 }
	Reason for the most recent chip reset. More...

Functions
std::string	idfxx::to_string (reset_reason r)
	Returns a string representation of a reset reason.
reset_reason	idfxx::last_reset_reason () noexcept
	Returns the reason for the most recent chip reset.
void	idfxx::restart ()
	Restart the chip immediately.
void	idfxx::register_shutdown_handler (void(*handler)())
	Registers a function to be called during chip shutdown/restart.
void	idfxx::unregister_shutdown_handler (void(*handler)())
	Unregisters a previously registered shutdown handler.
result< void >	idfxx::try_register_shutdown_handler (void(*handler)())
	Registers a function to be called during chip shutdown/restart.
result< void >	idfxx::try_unregister_shutdown_handler (void(*handler)())
	Unregisters a previously registered shutdown handler.
std::size_t	idfxx::free_heap_size () noexcept
	Returns the current free heap size in bytes.
std::size_t	idfxx::free_internal_heap_size () noexcept
	Returns the current free internal heap size in bytes.
std::size_t	idfxx::minimum_free_heap_size () noexcept
	Returns the minimum free heap size recorded since boot.

Detailed Description

Reset reason, restart, shutdown handlers, and heap information.

Enumeration Type Documentation

reset_reason

enum class idfxx::reset_reason : int

strong

Reason for the most recent chip reset.

auto reason = idfxx::last_reset_reason();
if (reason == idfxx::reset_reason::panic) {
    // Handle crash recovery
}

Enumerator
unknown	Reset reason could not be determined.
power_on	Power-on reset.
external	Reset by external pin (not applicable for ESP32).
software	Software reset via esp_restart.
panic	Software reset due to exception/panic.
interrupt_watchdog	Reset due to interrupt watchdog.
task_watchdog	Reset due to task watchdog.
watchdog	Reset due to other watchdog.
deep_sleep	Reset after exiting deep sleep mode.
brownout	Brownout reset (software or hardware).
sdio	Reset over SDIO.
usb	Reset by USB peripheral.
jtag	Reset by JTAG.
efuse	Reset due to efuse error.
power_glitch	Reset due to power glitch detected.
cpu_lockup	Reset due to CPU lock up.

Definition at line 38 of file system.hpp.

Function Documentation

free_heap_size()

std::size_t idfxx::free_heap_size ( )

inlinenoexcept

Returns the current free heap size in bytes.

Returns

The number of bytes available in the heap.

Definition at line 147 of file system.hpp.

free_internal_heap_size()

std::size_t idfxx::free_internal_heap_size ( )

inlinenoexcept

Returns the current free internal heap size in bytes.

Internal memory is directly accessible by the CPU and is typically used for performance-critical allocations.

Returns

The number of bytes available in internal heap.

Definition at line 159 of file system.hpp.

last_reset_reason()

reset_reason idfxx::last_reset_reason ( )

inlinenoexcept

Returns the reason for the most recent chip reset.

Returns

The reset reason.

Definition at line 72 of file system.hpp.

minimum_free_heap_size()

std::size_t idfxx::minimum_free_heap_size ( )

inlinenoexcept

Returns the minimum free heap size recorded since boot.

This is the "high water mark" — the lowest free heap level reached at any point during execution. Useful for diagnosing memory pressure.

Returns

The minimum number of free bytes recorded since boot.

Definition at line 171 of file system.hpp.

register_shutdown_handler()

void idfxx::register_shutdown_handler

(

void(*)()

handler

)

Registers a function to be called during chip shutdown/restart.

Shutdown handlers are called in reverse order of registration when esp_restart() is invoked.

Parameters

handler

Function pointer to the shutdown handler.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on failure.

restart()

void idfxx::restart ( )

inline

Restart the chip immediately.

Performs a software reset. This function does not return. Registered shutdown handlers are called before the restart occurs.

Definition at line 82 of file system.hpp.

to_string()

std::string idfxx::to_string

(

reset_reason

r

)

Returns a string representation of a reset reason.

Parameters

r	The reset reason to convert.

Returns

A descriptive string, or "unknown(N)" for unrecognized values.

try_register_shutdown_handler()

result< void > idfxx::try_register_shutdown_handler

(

void(*)()

handler

)

Registers a function to be called during chip shutdown/restart.

Shutdown handlers are called in reverse order of registration when esp_restart() is invoked.

Parameters

handler

Function pointer to the shutdown handler.

Returns

Success, or an error.

Return values

idfxx::errc::invalid_state

if the handler was already registered.

try_unregister_shutdown_handler()

result< void > idfxx::try_unregister_shutdown_handler

(

void(*)()

handler

)

Unregisters a previously registered shutdown handler.

Parameters

handler

Function pointer to the shutdown handler to remove.

Returns

Success, or an error.

Return values

idfxx::errc::invalid_state

if the handler was not registered.

unregister_shutdown_handler()

void idfxx::unregister_shutdown_handler

(

void(*)()

handler

)

Unregisters a previously registered shutdown handler.

Parameters

handler

Function pointer to the shutdown handler to remove.

Note

Only available when CONFIG_COMPILER_CXX_EXCEPTIONS is enabled in menuconfig.

Exceptions

std::system_error

on failure.