The code segment creates a child process which does some unspecified work. Meanwhile the parent loops performing calls to waitpid to monitor the status of the child. The loop terminates when child termination is detected. A call to the wait or waitpid function only returns status on an immediate child process of the calling process; that is, a child that was produced by a single fork call perhaps followed by an exec or other function calls from the parent.
If a child produces grandchildren by further use of fork , none of those grandchildren nor any of their descendants affect the behavior of a wait from the original parent process. To permit a library routine, such as system or pclose , to wait for its children without interfering with other terminated children for which the process has not waited.
#wait hashtag on Instagram • Photos and Videos
The first two of these facilities are based on the wait3 function provided by 4. The function uses the options argument, which is equivalent to an argument to wait3. Its name comes from 4. The third reason for the waitpid function is to permit independent sections of a process to spawn and wait for children without interfering with each other.
For example, the following problem occurs in developing a portable shell, or command interpreter:. On all historical implementations, the final pclose fails to reap the wait status of the popen. The status values are retrieved by macros, rather than given as specific bit encodings as they are in most historical implementations and thus expected by existing programs. This was necessary to eliminate a limitation on the number of signals an implementation can support that was inherent in the traditional encodings.
The interval defined by millisecondsTimeout elapses. Canceling the cancellationToken cancellation token has no effect on the running task unless it has also been passed the cancellation token and is prepared to handle cancellation. Passing the cancellationToken object to this method simply allows the wait to be canceled based on some condition. The following example illustrates the simple use of a cancellation token to cancel waiting for a task's completion.
A task is launched, calls the CancellationTokenSource. Cancel method to cancel any of the token source's cancellation tokens, and then delays for five seconds. Note that the task itself has not been passed the cancellation token and is not cancelable. The application thread calls the task's Task. Wait method to wait for the task to complete, but the wait is canceled once the cancellation token is cancelled and an OperationCanceledException is thrown.
The exception handler reports the exception and then sleeps for six seconds. As the output from the example shows, that delay allows the task to complete in the RanToCompletion state. The Wait CancellationToken method creates a cancelable wait; that is, it causes the current thread to wait until one of the following occurs:. The cancellation token is canceled. Passing the cancellationToken object to this method simply allows the wait to be canceled.
Wait Wait...Don't Tell Me!
The example uses the Wait Int32 method to wait for the application to complete within milliseconds. Wait Int32 is a synchronization method that causes the calling thread to wait for the current task instance to complete until one of the following occurs:.
The following example starts a task that generates one million random integers between 0 and and computes their mean. The example uses the Wait method to ensure that the task completes before the application terminates. Otherwise, because this is a console application, the example would terminate before the task can compute and display the mean. Wait is a synchronization method that causes the calling thread to wait until the current task has completed.
If the current task has not started execution, the Wait method attempts to remove the task from the scheduler and execute it inline on the current thread. If it is unable to do that, or if the current task has already started execution, it blocks the calling thread until the task completes.
Handbook writers universally denigrate wait on and prescribe wait for in writing. Our evidence from printed sources does not show a regional preference; it does show that the handbooks' advice is not based on current usage. White the staggering bill that waited on them at the white commissary downtown — Maya Angelou One reason for the continuing use of wait on may lie in its being able to suggest protracted or irritating waits better than wait for. Lindbergh the boredom of black Africans sitting there, waiting on the whims of a colonial bureaucracy — Vincent Canby doesn't care to sit around waiting on a House that's virtually paralyzed — Glenn A.
Briere Wait on is less common than wait for , but if it seems natural, there is no reason to avoid it. These example sentences are selected automatically from various online news sources to reflect current usage of the word 'wait.
See more words from the same century. See the full definition for wait in the English Language Learners Dictionary. Wait a second—I have a better idea. There's a package waiting for you.
Wait Wait Naked and Ashamed: Peter Sagal
This sense of wait is usually used in the expression lie in wait. Words that rhyme with wait. Translation of wait for Spanish Speakers. Translation of wait for Arabic Speakers.
Encyclopedia article about wait. What made you want to look up wait? Please tell us where you read or heard it including the quote, if possible.
wait(2) - Linux man page
Test Your Knowledge - and learn some interesting things along the way. Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free! What origins we bring to you and your kin. A word with surprisingly literal origins.
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