24.12. POSIX Initialization Thread Configuration — RTEMS Classic API Guide 5.4-rc2 (21st August 2026) documentation

# 24.12. POSIX Initialization Thread Configuration

This section describes configuration options related to the POSIX initialization thread.

## 24.12.1. CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT

CONSTANT:

  `CONFIGURE_POSIX_INIT_THREAD_ENTRY_POINT`

OPTION TYPE:

  This configuration option is an initializer define.

DEFAULT VALUE:

  The default value is `POSIX_Init`.

VALUE CONSTRAINTS:

  The value of this configuration option shall be defined to a valid function pointer of the type `void *( *entry_point )( void * )`.

DESCRIPTION:

  The value of this configuration option initializes the entry point of the POSIX API initialization thread.

NOTES:

  The application shall provide the function referenced by this configuration option.

## 24.12.2. CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE

CONSTANT:

  `CONFIGURE_POSIX_INIT_THREAD_STACK_SIZE`

OPTION TYPE:

  This configuration option is an integer define.

DEFAULT VALUE:

  The default value is CONFIGURE_MINIMUM_POSIX_THREAD_STACK_SIZE.

VALUE CONSTRAINTS:

  The value of this configuration option shall satisfy all of the following constraints:

  - It shall be greater than or equal to CONFIGURE_MINIMUM_TASK_STACK_SIZE.

  - It shall be small enough so that the task stack space calculation carried out by `<rtems/confdefs.h>` does not overflow an integer of type `uintptr_t`.

DESCRIPTION:

  The value of this configuration option defines the thread stack size of the POSIX API initialization thread.

NOTES:

  None.

## 24.12.3. CONFIGURE_POSIX_INIT_THREAD_TABLE

CONSTANT:

  `CONFIGURE_POSIX_INIT_THREAD_TABLE`

OPTION TYPE:

  This configuration option is a boolean feature define.

DEFAULT CONFIGURATION:

  If this configuration option is undefined, then the described feature is not enabled.

DESCRIPTION:

  In case this configuration option is defined, then exactly one POSIX initialization thread is configured.

NOTES:

  The application shall define exactly one of the following configuration options

  - CONFIGURE_RTEMS_INIT_TASKS_TABLE,

  - CONFIGURE_POSIX_INIT_THREAD_TABLE, or

  - CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION

  otherwise a compile time error in the configuration file will occur.