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iv_timer(3) [debian man page]

iv_timer(3)						    ivykis programmer's manual						       iv_timer(3)

NAME
iv_timer_register, iv_timer_unregister, iv_timer_registered - deal with ivykis timers SYNOPSIS
#include <iv.h> struct iv_timer { struct timespec expires; void *cookie; void (*handler)(void *); }; void IV_TIMER_INIT(struct iv_timer *timer); void iv_timer_register(struct iv_timer *timer); void iv_timer_unregister(struct iv_timer *timer); int iv_timer_registered(struct iv_timer *timer); DESCRIPTION
The functions iv_timer_register and iv_timer_unregister register, respectively unregister, a timer with the current thread's ivykis event loop. iv_timer_registered on a timer returns true if that timer is currently registered with ivykis. When a timer that is registered becomes 'ready', due to the current system clock value becoming greater than or equal to the timer's ->expires member field, the callback function specified by ->handler is called in the thread that the timer was registered in, with ->cookie as its first and sole argument. When this happens, the timer is transparently unregistered. The application is allowed to change the ->cookie and ->handler members at any time. The application is not allowed to change the ->expires member while the timer is registered. A given struct iv_timer can only be registered in one thread at a time, and a timer can only be unregistered in the thread that it was reg- istered from. There is no limit on the number of timers registered at once. See iv_examples(3) for programming examples. SEE ALSO
ivykis(3), iv_examples(3) ivykis 2010-08-15 iv_timer(3)

Check Out this Related Man Page

ivykis(3)						    ivykis programmer's manual							 ivykis(3)

NAME
ivykis - library for asynchronous I/O readiness notification DESCRIPTION
ivykis is a library for asynchronous I/O readiness notification. It is a thin, portable wrapper around OS-provided mechanisms such as epoll_create(2), kqueue(2), poll(2), poll(7d) (/dev/poll), port_create(3C) and select(2). ivykis was mainly designed for building high-performance network applications, but can be used in any event-driven application that uses poll(2)able file descriptors as its event sources. While some programming models dictate using blocking I/O and starting a thread per event source, programs written to the ivykis API are generally single-threaded (or use only a small number of threads), and never block on I/O. All input and output is done in a nonblocking fashion, with I/O readiness notifications delivered via callback functions. The two main event sources in ivykis are file descriptors and timers. File descriptors generate an event when they become readable or writable or trigger an error condition, while timers generate an event when the system time increments past a certain pre-set time. Events associated with file descriptors are level-triggered -- a callback function set up to handle a certain file descriptor event will be called repeatedly until the condition generating the event has been cleared. As mentioned, applications using ivykis are generally single-threaded. Event callbacks are strictly serialised within a thread, and non- preemptible. This mostly removes the need for locking of shared data, and generally simplifies writing applications. Each thread that uses ivykis has its own file descriptors and timers, and runs a separate event loop. In ivykis, all code that is not initialization code runs from callback functions. Callback functions are not allowed to block. If a par- ticular piece of code wants to perform a certain operation that can block, it either has to schedule it to run in a separate thread, or it has to perform the operation in a nonblocking fashion instead. For example, registering an input callback function instead of blocking on a read, registering a timer instead of calling sleep(2), etc. In case of an internal error, ivykis will use iv_fatal(3) to report the error. The application can provide a custom fatal error handler by calling iv_set_fatal_msg_handler(3). SEE ALSO
iv_examples(3), iv_fatal(3), iv_fd(3), iv_timer(3), iv_task(3), iv_init(3), iv_main(3), iv_time(3) ivykis 2010-08-15 ivykis(3)

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