Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

tis_cond_init(3) [osf1 man page]

tis_cond_init(3)					     Library Functions Manual						  tis_cond_init(3)

NAME
tis_cond_init - Initializes a condition variable. LIBRARY
Standard C Library (libc.so, libc.a) SYNOPSIS
#include <tis.h> int tis_cond_init( pthread_cond_t *cond); STANDARDS
None PARAMETERS
Address of the condition variable (passed by reference) to be initialized. DESCRIPTION
This routine initializes a condition variable (cond) with the DECthreads default condition variable attributes. A condition variable is a synchronization object used in conjunction with a mutex. A mutex controls access to shared data. When threads are present, a condition variable allows threads to wait for data to enter a defined state. For more information about actions taken when threads are present, refer to the pthread_cond_init(3) description. Your program can use the macro PTHREAD_COND_INITIALIZER to initialize statically allocated condition variables to the DECthreads default condition variable attributes. Static initialization can be used only for a condition variable with storage class extern or static - auto- matic (stack local) objects must be initialized by calling tis_cond_destroy(3). Use this macro as follows: pthread_cond_t condition = PTHREAD_COND_INITIALIZER When statically initialized, a condition variable should not also be initialized using tis_cond_init(3). RETURN VALUES
If an error condition occurs, the following occurs: The routine returns an integer value indicating the type of error. The condition vari- able is not initialized. The contents of condition variable cond are undefined. The possible return values are as follows: Successful completion. The system lacks the necessary resources to initialize another condition variable, or The system-imposed limit on the total number of condition variables under execution by a single user is exceeded. The imple- mentation has detected an attempt to reinitialize the object referenced by cond, a previously initialized, but not yet destroyed condition variable. The value specified by attr is not a valid condition variable. Insufficient memory exists to initialize the condition variable. ERRORS
None RELATED INFORMATION
Functions: tis_cond_broadcast(3), tis_cond_destroy(3), tis_cond_signal(3), tis_cond_wait(3) Manuals: Guide to DECthreads and Programmer's Guide delim off tis_cond_init(3)

Check Out this Related Man Page

pthread_cond_init(3C)					   Standard C Library Functions 				     pthread_cond_init(3C)

NAME
pthread_cond_init, pthread_cond_destroy - initialize or destroy condition variables SYNOPSIS
cc -mt [ flag... ] file... -lpthread [ library... ] #include <pthread.h> int pthread_cond_init(pthread_cond_t *restrict cond, const pthread_condattr_t *restrict attr); int pthread_cond_destroy(pthread_cond_t *cond pthread_cond_t cond= PTHREAD_COND_INITIALIZER; DESCRIPTION
The function pthread_cond_init() initializes the condition variable referenced by cond with attributes referenced by attr. If attr is NULL, the default condition variable attributes are used; the effect is the same as passing the address of a default condition variable attributes object. See pthread_condattr_init(3C). Upon successful initialization, the state of the condition variable becomes initialized. Attempting to initialize an already initialized condition variable results in undefined behavior. The function pthread_cond_destroy() destroys the given condition variable specified by cond; the object becomes, in effect, uninitialized. An implementation may cause pthread_cond_destroy() to set the object referenced by cond to an invalid value. A destroyed condition variable object can be re-initialized using pthread_cond_init(); the results of otherwise referencing the object after it has been destroyed are undefined. It is safe to destroy an initialized condition variable upon which no threads are currently blocked. Attempting to destroy a condition variable upon which other threads are currently blocked results in undefined behavior. In cases where default condition variable attributes are appropriate, the macro PTHREAD_COND_INITIALIZER can be used to initialize condi- tion variables that are statically allocated. The effect is equivalent to dynamic initialization by a call to pthread_cond_init() with parameter attr specified as NULL, except that no error checks are performed. RETURN VALUES
If successful, the pthread_cond_init() and pthread_cond_destroy() functions return 0. Otherwise, an error number is returned to indicate the error. The EBUSY and EINVAL error checks, if implemented, act as if they were performed immediately at the beginning of processing for the function and caused an error return prior to modifying the state of the condition variable specified by cond. ERRORS
The pthread_cond_init() function will fail if: EAGAIN The system lacked the necessary resources (other than memory) to initialize another condition variable. ENOMEM Insufficient memory exists to initialize the condition variable. The pthread_cond_init() function may fail if: EBUSY The implementation has detected an attempt to re-initialize the object referenced by cond, a previously initialized, but not yet destroyed, condition variable. EINVAL The value specified by attr is invalid. The pthread_cond_destroy() function may fail if: EBUSY The implementation has detected an attempt to destroy the object referenced by cond while it is referenced (for example, while being used in a pthread_cond_wait() or pthread_cond_timedwait()) by another thread. EINVAL The value specified by cond is invalid. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ SEE ALSO
pthread_cond_signal(3C), pthread_cond_broadcast(3C), pthread_cond_wait(3C), pthread_cond_timedwait(3C), pthread_condattr_init(3C), attributes(5), condition(5), standards(5) SunOS 5.11 23 Mar 2005 pthread_cond_init(3C)
Man Page

Featured Tech Videos