---
name: "pthread_mutexattr_gettype"
section: "3p"
platform: "linux"
package: "man-pages"
version: "6.19-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/pthread_mutexattr_gettype/3p"
---

# pthread\_mutexattr\_gettype(3p)

get and set the mutex type attribute

## PROLOG

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

## NAME

pthread\_mutexattr\_gettype, pthread\_mutexattr\_settype — get and set the mutex type attribute

## SYNOPSIS

```
#include <pthread.h>
```

int pthread\_mutexattr\_gettype(const pthread\_mutexattr\_t \*restrict *attr*,\
     int \*restrict *type*); int pthread\_mutexattr\_settype(pthread\_mutexattr\_t \**attr*, int *type*);

## DESCRIPTION

The *pthread\_mutexattr\_gettype*() and *pthread\_mutexattr\_settype*() functions, respectively, shall get and set the mutex *type* attribute. This attribute is set in the *type* parameter to these functions. The default value of the *type* attribute is PTHREAD\_MUTEX\_DEFAULT.

The type of mutex is contained in the *type* attribute of the mutex attributes. Valid mutex types include:

PTHREAD\_MUTEX\_NORMAL PTHREAD\_MUTEX\_ERRORCHECK PTHREAD\_MUTEX\_RECURSIVE PTHREAD\_MUTEX\_DEFAULT

The mutex type affects the behavior of calls which lock and unlock the mutex. See *pthread\_mutex\_lock()* for details. An implementation may map PTHREAD\_MUTEX\_DEFAULT to one of the other mutex types.

The behavior is undefined if the value specified by the *attr* argument to *pthread\_mutexattr\_gettype*() or *pthread\_mutexattr\_settype*() does not refer to an initialized mutex attributes object.

## RETURN VALUE

Upon successful completion, the *pthread\_mutexattr\_gettype*() function shall return zero and store the value of the *type* attribute of *attr* into the object referenced by the *type* parameter. Otherwise, an error shall be returned to indicate the error.

If successful, the *pthread\_mutexattr\_settype*() function shall return zero; otherwise, an error number shall be returned to indicate the error.

## ERRORS

The *pthread\_mutexattr\_settype*() function shall fail if:

- **EINVAL**

  The value *type* is invalid.

These functions shall not return an error code of **\[EINTR\]**.

*The following sections are informative.*

## EXAMPLES

None.

## APPLICATION USAGE

It is advised that an application should not use a PTHREAD\_MUTEX\_RECURSIVE mutex with condition variables because the implicit unlock performed for a *pthread\_cond\_timedwait*() or *pthread\_cond\_wait*() may not actually release the mutex (if it had been locked multiple times). If this happens, no other thread can satisfy the condition of the predicate.

## RATIONALE

If an implementation detects that the value specified by the *attr* argument to *pthread\_mutexattr\_gettype*() or *pthread\_mutexattr\_settype*() does not refer to an initialized mutex attributes object, it is recommended that the function should fail and report an **\[EINVAL\]** error.

## FUTURE DIRECTIONS

None.

## SEE ALSO

*pthread\_cond\_timedwait()*, *pthread\_mutex\_lock()*

The Base Definitions volume of POSIX.1‐2017, ***\<pthread.h\>***

## COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting\_bugs.html .