.TH "evthread_condition_callbacks" 3 "Tue Jan 31 2017" "libevent" \" -*- nroff -*- .ad l .nh .SH NAME evthread_condition_callbacks \- This structure describes the interface a threading library uses for condition variables\&. .SH SYNOPSIS .br .PP .PP \fC#include \fP .SS "Data Fields" .in +1c .ti -1c .RI "void *(* \fBalloc_condition\fP )(unsigned condtype)" .br .RI "\fIFunction to allocate and initialize a new condition variable\&. \fP" .ti -1c .RI "int \fBcondition_api_version\fP" .br .RI "\fIThe current version of the conditions API\&. \fP" .ti -1c .RI "void(* \fBfree_condition\fP )(void *cond)" .br .RI "\fIFunction to free a condition variable\&. \fP" .ti -1c .RI "int(* \fBsignal_condition\fP )(void *cond, int broadcast)" .br .RI "\fIFunction to signal a condition variable\&. \fP" .ti -1c .RI "int(* \fBwait_condition\fP )(void *cond, void *lock, const struct timeval *timeout)" .br .RI "\fIFunction to wait for a condition variable\&. \fP" .in -1c .SH "Detailed Description" .PP This structure describes the interface a threading library uses for condition variables\&. It's used to tell evthread_set_condition_callbacks how to use locking on this platform\&. .SH "Field Documentation" .PP .SS "void*(* evthread_condition_callbacks::alloc_condition) (unsigned condtype)" .PP Function to allocate and initialize a new condition variable\&. Returns the condition variable on success, and NULL on failure\&. The 'condtype' argument will be 0 with this API version\&. .SS "int evthread_condition_callbacks::condition_api_version" .PP The current version of the conditions API\&. Set this to EVTHREAD_CONDITION_API_VERSION .SS "void(* evthread_condition_callbacks::free_condition) (void *cond)" .PP Function to free a condition variable\&. .SS "int(* evthread_condition_callbacks::signal_condition) (void *cond, int broadcast)" .PP Function to signal a condition variable\&. If 'broadcast' is 1, all threads waiting on 'cond' should be woken; otherwise, only on one thread is worken\&. Should return 0 on success, -1 on failure\&. This function will only be called while holding the associated lock for the condition\&. .SS "int(* evthread_condition_callbacks::wait_condition) (void *cond, void *lock, const struct timeval *timeout)" .PP Function to wait for a condition variable\&. The lock 'lock' will be held when this function is called; should be released while waiting for the condition to be come signalled, and should be held again when this function returns\&. If timeout is provided, it is interval of seconds to wait for the event to become signalled; if it is NULL, the function should wait indefinitely\&. .PP The function should return -1 on error; 0 if the condition was signalled, or 1 on a timeout\&. .SH "Author" .PP Generated automatically by Doxygen for libevent from the source code\&.