rwlock_init

Initializes a reader-writer lock.

Library:LibC

Classification:UNIX International

Service:Synchronization

Syntax

  #include <synch.h>
   
  int   rwlock_init  (
     rwlock_t   *rwlp,
     int         type,
     void       *arg );

rwlp

(IN) Points to the reader-writer lock to be initialized.

type

(IN) Specifies the type of mutex with one of the following flags:

Flag	Value	Description
USYNC_THREAD	0	The lock is known only to the owning process.
USYNC_PROCESS	1	Unsupported. The lock can be shared between processes.

arg

(IN) Reserved for future use. Set to NULL

If successful, returns zero; otherwise, returns a nonzero error code:

Decimal	Constant	Description
79	ENOTSUP	The type parameter contains an invalid value.

Mutually exclusive locks are acquired by threads on behalf of the context that they might be hosting.