NAME

pthread_attr_getguardsize − Obtains the guardsize attribute of the specified thread attributes object. 

LIBRARY

DECthreads POSIX 1003.1c Library (libpthread.so)

SYNOPSIS

#include <pthread.h>

int pthread_attr_getguardsize_np(
                const pthread_attr_t  ∗attr,
                size_t                ∗guardsize);

STANDARDS

Interfaces documented on this reference page conform to industry standards as follows:

IEEE Std 1003.1c-1995, POSIX System Application Program Interface

PARAMETERS

attrAddress of the thread attributes object whose guardsize attribute is obtained. 

guardsizeReceives the value of the guardsize attribute of the thread attributes object specified by attr. 

DESCRIPTION

This routine obtains the value of the guardsize attribute of the thread attributes object specified in the attr argument and stores it in the location specified by the guardsize argument.  The specified attributes object must already be initialized at the time this routine is called. 

When creating a thread, use a thread attributes object to specify nondefault values for thread attributes.  The guardsize attribute of a thread attributes object specifies the minimum size (in bytes) of the guard area for the stack of a new thread. 

A guard area can help a multithreaded program detect overflow of a thread’s stack. A guard area is a region of no-access memory that DECthreads allocates at the overflow end of the thread’s stack. When any thread attempts to access a memory location within this region, a memory addressing violation occurs. 

NOTES

The value of the guardsize attribute of a particular thread attributes object does not necessarily correspond to the actual size of the guard area of any existing thread in your multithreaded program. 

RETURN VALUES

If an error condition occurs, this routine returns an integer value indicating the type of error.  Possible return values are as follows:

0Successful completion. 

[EINVAL]The value specified by attr is invalid. 

ERRORS

None

RELATED INFORMATION

Functions: pthread_attr_init(3), pthread_create(3)
 

Manuals: Guide to DECthreads and Programmer’s Guide