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pthread_attr_getstackprealloc()

Get the size of memory to preallocate for a stack

Synopsis:

#include <pthread.h>

int pthread_attr_getstackprealloc(const pthread_attr_t * attr,
                                  size_t *stacksize);

Arguments:

attr: A pointer to the pthread_attr_t structure that defines the attributes to use when creating new threads. For more information, see pthread_attr_init().
stacksize: A pointer to a location where the function can store the size (of the stack).

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

The pthread_attr_getstackprealloc() function gets the value of the memory size attribute from the attribute structure attr to preallocate for a MAP_LAZY stack. By default, the system allocates sysconf(_SC_PAGESIZE) bytes of physical memory for initial stack reference. This function allows you to change this default memory size, if you know that a thread will need more stack space. Semantically, there is no difference in operation, but the memory manager attempts to implement an efficient use of memory management unit hardware (e.g. a larger page size in the page entry table) for the stack if it knows upfront that more memory will be required.

This function was added in the QNX Neutrino Core OS 6.3.2.

Returns:

EOK: Success.

Classification:

QNX Neutrino

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	Yes
Thread	Yes