AIX Version 4.3 Base Operating System and Extensions Technical Reference, Volume

pthread_attr_init Subroutine


Creates a thread attributes object and initializes it with default values.


Threads Library (libpthreads.a)



int pthread_attr_init (attr)

pthread_attr_t *attr;


The pthread_attr_init subroutine creates a new thread attributes object attr. The
new thread attributes object is initialized with the following default values:

Always initialized

Attribute Default value


Always Initialized

Attribute Default value

Contention-scope PTHREAD_SCOPE_PROCESS the default ensures compatibility with
implementations that do not support this POSIX option.


Schedparam A sched_param structure which sched_prio field is set to 1, the least
favored priority.

Schedpolicy SCHED_OTHER

Always Initialized

Attribute Default value


Guardsize PAGESIZE

The resulting attribute object (possibly modified by setting individual attribute
values), when used by pthread_create, defines the attributes of the thread
created. A single attributes object can be used in multiple simultaneous calls to


attr Specifies the thread attributes object to be created.

Return Values

Upon successful completion, the new thread attributes object is filled with
default values and returned via the attr parameter, and 0 is returned. Otherwise,
an error code is returned.

Error Codes

The pthread_attr_init subroutine is unsuccessful if the following is true:

EINVAL The attr parameter is not valid.

ENOMEM There is not sufficient memory to create the thread attribute object.

This function will not return an error code of [EINTR].

Implementation Specifics

This subroutine is part of the Base Operating System (BOS) Runtime.

Related Information

The pthread_attr_setdetachstate subroutine, pthread_attr_setstackaddr subroutine,
pthread_attr_setstacksize subroutine, pthread_create subroutine,
pthread_attr_destroy and pthread_attr_setguardsize subroutine.

The pthread.h file.

Creating Threads in AIX Version 4.3 General Programming Concepts: Writing and
Debugging Programs.

Threads Library Options and Threads Library Quick Reference in AIX Version 4.3
General Programming Concepts: Writing and Debugging Programs.