.TH "globus_cond" 3 "Version 18.14" "globus_common" \" -*- nroff -*-
.ad l
.nh
.SH NAME
globus_cond \- Condition Variables
.PP
 \- Condition Variables\&.  

.SH SYNOPSIS
.br
.PP
.SS "Data Structures"

.in +1c
.ti -1c
.RI "union \fBglobus_cond_t\fP"
.br
.RI "Condition variable\&. "
.ti -1c
.RI "union \fBglobus_condattr_t\fP"
.br
.RI "Condition variable attribute\&. "
.in -1c
.SS "Functions"

.in +1c
.ti -1c
.RI "int \fBglobus_cond_init\fP (\fBglobus_cond_t\fP *cond, \fBglobus_condattr_t\fP *attr)"
.br
.RI "Initialize a condition variable
.PP
The \fBglobus_cond_init()\fP function creates a condition variable that can be used for event signalling between threads\&. "
.ti -1c
.RI "int \fBglobus_cond_destroy\fP (\fBglobus_cond_t\fP *cond)"
.br
.RI "Destroy a condition variable\&. "
.ti -1c
.RI "int \fBglobus_cond_wait\fP (\fBglobus_cond_t\fP *cond, \fBglobus_mutex_t\fP *mutex)"
.br
.RI "Wait for a condition to be signalled\&. "
.ti -1c
.RI "int \fBglobus_cond_timedwait\fP (\fBglobus_cond_t\fP *cond, \fBglobus_mutex_t\fP *mutex, globus_abstime_t *abstime)"
.br
.RI "Wait for a condition to be signalled\&. "
.ti -1c
.RI "int \fBglobus_cond_signal\fP (\fBglobus_cond_t\fP *cond)"
.br
.RI "Signal a condition to a thread\&. "
.ti -1c
.RI "int \fBglobus_cond_broadcast\fP (\fBglobus_cond_t\fP *cond)"
.br
.RI "Signal a condition to multiple threads\&. "
.ti -1c
.RI "int \fBglobus_condattr_init\fP (\fBglobus_condattr_t\fP *cond_attr)"
.br
.RI "Initialize a condition variable attribute\&. "
.ti -1c
.RI "int \fBglobus_condattr_destroy\fP (\fBglobus_condattr_t\fP *cond_attr)"
.br
.RI "Destroy a condition attribute\&. "
.ti -1c
.RI "int \fBglobus_condattr_setspace\fP (\fBglobus_condattr_t\fP *cond_attr, int space)"
.br
.RI "Set callback space associated with a condition variable attribute
.PP
The \fBglobus_condattr_setspace()\fP function sets the callback space to use with condition variables created with this attribute\&. Callback spaces are used to control how callbacks are issued to different threads\&. See \fBCallback Spaces \fP for more information on callback spaces\&. "
.ti -1c
.RI "int \fBglobus_condattr_getspace\fP (\fBglobus_condattr_t\fP *cond_attr, int *space)"
.br
.RI "Get callback space associated with a condition variable attribute
.PP
The \fBglobus_condattr_getspace()\fP function copies the value of the callback space associated with a condition variable attribute to the integer pointed to by the \fIspace\fP parameter\&. "
.in -1c
.SH "Detailed Description"
.PP 
Condition Variables\&. 

The \fBglobus_cond_t\fP provides condition variables for signalling events between threads interested in particular state\&. One or many threads may wait on a condition variable until it is signalled, at which point they can attempt to lock a mutex related to that condition's state and process the event\&.
.PP
In a non-threaded model, the condition variable wait operations are used to poll the event driver to handle any operations that have been scheduled for execution by the globus_callback system or I/O system\&. In this way, applications written to use those systems to handle nonblocking operations will work with either a threaded or nonthreaded runtime choice\&. 
.SH "Function Documentation"
.PP 
.SS "int globus_cond_broadcast (\fBglobus_cond_t\fP * cond)"

.PP
Signal a condition to multiple threads\&. The \fBglobus_cond_signal()\fP function signals a condition as occurring\&. This will unblock all threads waiting for that condition\&.
.PP
\fBParameters\fP
.RS 4
\fIcond\fP A pointer to the condition variable to signal\&. 
.RE
.PP
\fBReturns\fP
.RS 4
Upon success, \fBglobus_cond_broadcast()\fP returns GLOBUS_SUCCESS\&. If an error occurs, \fBglobus_cond_broadcast()\fP returns an implementation-specific non-zero error code\&. 
.RE
.PP

.SS "int globus_cond_destroy (\fBglobus_cond_t\fP * cond)"

.PP
Destroy a condition variable\&. The \fBglobus_cond_destroy()\fP function destroys the condition variable pointed to by its \fIcond\fP parameter\&. After a condition variable is destroyed it may no longer be used unless it is again initialized by \fBglobus_cond_init()\fP\&.
.PP
\fBParameters\fP
.RS 4
\fIcond\fP The condition variable to destroy\&. 
.RE
.PP
\fBReturns\fP
.RS 4
On success, \fBglobus_cond_destroy()\fP returns GLOBUS_SUCCESS\&. Otherwise, a non-zero implementation-specific error value is returned\&. 
.RE
.PP

.SS "int globus_cond_init (\fBglobus_cond_t\fP * cond, \fBglobus_condattr_t\fP * attr)"

.PP
Initialize a condition variable
.PP
The \fBglobus_cond_init()\fP function creates a condition variable that can be used for event signalling between threads\&. 
.PP
\fBParameters\fP
.RS 4
\fIcond\fP Pointer to the condition variable to initialize\&. 
.br
\fIattr\fP Condition variable attributes\&.
.RE
.PP
\fBReturns\fP
.RS 4
On success, \fBglobus_cond_init()\fP initializes the condition variable and returns GLOBUS_SUCCESS\&. Otherwise, a non-0 value is returned\&. 
.RE
.PP

.SS "int globus_cond_signal (\fBglobus_cond_t\fP * cond)"

.PP
Signal a condition to a thread\&. The \fBglobus_cond_signal()\fP function signals a condition as occurring\&. This will unblock at least one thread waiting for that condition\&.
.PP
\fBParameters\fP
.RS 4
\fIcond\fP A pointer to the condition variable to signal\&. 
.RE
.PP
\fBReturns\fP
.RS 4
Upon success, \fBglobus_cond_signal()\fP returns GLOBUS_SUCCESS\&. If an error occurs, \fBglobus_cond_signal()\fP returns an implementation-specific non-zero error code\&. 
.RE
.PP

.SS "int globus_cond_timedwait (\fBglobus_cond_t\fP * cond, \fBglobus_mutex_t\fP * mutex, globus_abstime_t * abstime)"

.PP
Wait for a condition to be signalled\&. The \fBglobus_cond_timedwait()\fP function atomically unlocks the mutex pointed to by the \fImutex\fP parameter and blocks the current thread until either the condition variable pointed to by \fIcond\fP is signalled by another thread or the current time exceeds the value pointed to by the \fIabstime\fP parameter\&. If the timeout occurs before the condition is signalled, \fBglobus_cond_timedwait()\fP returns ETIMEDOUT\&. Behavior is undefined if \fBglobus_cond_timedwait()\fP is called with the mutex pointed to by the \fImutex\fP variable unlocked\&.
.PP
\fBParameters\fP
.RS 4
\fIcond\fP The condition variable to wait for\&. 
.br
\fImutex\fP The mutex associated with the condition state\&. 
.br
\fIabstime\fP The absolute time to wait until\&.
.RE
.PP
\fBReturns\fP
.RS 4
On success, \fBglobus_cond_timedwait()\fP unlocks the mutex and blocks the current thread until it has been signalled, returning GLOBUS_SUCCES\&. If a timeout occurs before signal, \fBglobus_cond_timedwait()\fP unlocks the mutex and returns ETIMEDOUT\&. Otherwise, \fBglobus_cond_timedwait()\fP returns an implementation-specific non-zero error value\&. 
.RE
.PP

.SS "int globus_cond_wait (\fBglobus_cond_t\fP * cond, \fBglobus_mutex_t\fP * mutex)"

.PP
Wait for a condition to be signalled\&. The \fBglobus_cond_wait()\fP function atomically unlocks the mutex pointed to by the \fImutex\fP parameter and blocks the current thread until the condition variable pointed to by \fIcond\fP is signalled by either \fBglobus_cond_signal()\fP or \fBglobus_cond_broadcast()\fP\&. Behavior is undefined if \fBglobus_cond_wait()\fP is called with the mutex pointed to by the \fImutex\fP variable unlocked\&.
.PP
\fBParameters\fP
.RS 4
\fIcond\fP The condition variable to wait for\&. 
.br
\fImutex\fP The mutex associated with the condition state\&.
.RE
.PP
\fBReturns\fP
.RS 4
On success, \fBglobus_cond_wait()\fP unlocks the mutex and blocks the current thread until it has been signalled, returning GLOBUS_SUCCES\&. Otherwise, \fBglobus_cond_wait()\fP returns an implementation-specific non-zero error value\&. 
.RE
.PP

.SS "int globus_condattr_destroy (\fBglobus_condattr_t\fP * cond_attr)"

.PP
Destroy a condition attribute\&. The \fBglobus_condattr_destroy()\fP function destroys the condition variable attribute structure pointed to by its \fIcond_attr\fP parameter\&.
.PP
\fBParameters\fP
.RS 4
\fIcond_attr\fP Attribute structure to destroy\&.
.RE
.PP
\fBReturns\fP
.RS 4
Upon success, \fBglobus_condattr_destroy()\fP returns GLOBUS_SUCCESS and modifies the attribute pointed to by \fIcond_attr\fP\&. If an error occurs, \fBglobus_condattr_destroy()\fP returns an implementation-specific non-zero error code\&. 
.RE
.PP

.SS "int globus_condattr_getspace (\fBglobus_condattr_t\fP * cond_attr, int * space)"

.PP
Get callback space associated with a condition variable attribute
.PP
The \fBglobus_condattr_getspace()\fP function copies the value of the callback space associated with a condition variable attribute to the integer pointed to by the \fIspace\fP parameter\&. 
.PP
\fBParameters\fP
.RS 4
\fIcond_attr\fP Condition variable attribute to modify\&. 
.br
\fIspace\fP Pointer to an integer to be set to point to the callback space associated with cond_attr\&.
.RE
.PP
\fBReturns\fP
.RS 4
On success, \fBglobus_condattr_getspace()\fP returns GLOBUS_SUCCESS and modifies the value pointed to by \fIspace\fP to refer to the callback space associated with \fIcond_attr\fP\&. If an error occurs, \fBglobus_condattr_getspace()\fP returns an implementation-specific non-zero error code\&. 
.RE
.PP

.SS "int globus_condattr_init (\fBglobus_condattr_t\fP * cond_attr)"

.PP
Initialize a condition variable attribute\&. The \fBglobus_condattr_init()\fP function initializes the condition variable attribute structure pointed to by its \fIcond_attr\fP parameter to the system default values\&.
.PP
\fBParameters\fP
.RS 4
\fIcond_attr\fP Attribute structure to initialize\&.
.RE
.PP
\fBReturns\fP
.RS 4
Upon success, \fBglobus_condattr_init()\fP returns GLOBUS_SUCCESS and modifies the attribute pointed to by \fIcond_attr\fP\&. If an error occurs, \fBglobus_condattr_init()\fP returns an implementation-specific non-zero error code\&. 
.RE
.PP

.SS "int globus_condattr_setspace (\fBglobus_condattr_t\fP * cond_attr, int space)"

.PP
Set callback space associated with a condition variable attribute
.PP
The \fBglobus_condattr_setspace()\fP function sets the callback space to use with condition variables created with this attribute\&. Callback spaces are used to control how callbacks are issued to different threads\&. See \fBCallback Spaces \fP for more information on callback spaces\&. 
.PP
\fBParameters\fP
.RS 4
\fIcond_attr\fP Condition variable attribute to modify\&. 
.br
\fIspace\fP Callback space to associate with the attribute\&.
.RE
.PP
\fBReturns\fP
.RS 4
On success, \fBglobus_condattr_setspace()\fP returns GLOBUS_SUCCESS and adds a reference to the callback space to the condition variable attribute\&. If an error occurs, \fBglobus_condattr_setspace()\fP returns an implementation-specific non-zero error code\&. 
.RE
.PP

.SH "Author"
.PP 
Generated automatically by Doxygen for globus_common from the source code\&.