---
name: "pthread_cond_init"
section: "3"
platform: "macos"
package: "libpthread"
version: "539.100.4"
release: "macOS 26.5"
platforms: ["linux", "freebsd", "macos"]
url: "https://new.carta.tech/pthread_cond_init"
---

# pthread\_cond\_init(3)

create a condition variable

## NAME

**pthread\_cond\_init** – create a condition variable

## SYNOPSIS

**#include \<pthread.h\>**

*int*\

**pthread\_cond\_init**(*pthread\_cond\_t \*cond*, *const pthread\_condattr\_t \*attr*);

## DESCRIPTION

The **pthread\_cond\_init**() function creates a new condition variable, with attributes specified with *attr*. If *attr* is NULL the default attributes are used.

## RETURN VALUES

If successful, the **pthread\_cond\_init**() function will return zero and put the new condition variable id into *cond*, otherwise an error number will be returned to indicate the error.

## ERRORS

The **pthread\_cond\_init**() function will fail if:

- \[EINVAL\]

  The value specified by *attr* is invalid.

- \[ENOMEM\]

  The process cannot allocate enough memory to create another condition variable.

- \[EAGAIN\]

  The system temporarily lacks the resources to create another condition variable.

## SEE ALSO

[pthread\_cond\_broadcast(3)](/pthread_cond_broadcast/3.md), [pthread\_cond\_destroy(3)](/pthread_cond_destroy/3.md), [pthread\_cond\_signal(3)](/pthread_cond_signal/3.md), [pthread\_cond\_timedwait(3)](/pthread_cond_timedwait/3.md), [pthread\_cond\_wait(3)](/pthread_cond_wait/3.md), [pthread\_condattr(3)](/pthread_condattr/3.md)

## STANDARDS

The **pthread\_cond\_init**() function conforms to ISO/IEC 9945-1:1996 (“POSIX.1”).