What does Wnohang mean?
WNOHANG. This flag specifies that waitpid should return immediately instead of waiting, if there is no child process ready to be noticed. WUNTRACED. This flag specifies that waitpid should report the status of any child processes that have been stopped as well as those that have terminated.
What does Wuntraced do?
WUNTRACED The status of any child processes specified by pid that are stopped, and whose status has not yet been reported since they stopped, shall also be reported to the requesting process.
What is Waitpid?
The waitpid() function allows the calling thread to obtain status information for one of its child processes. The calling thread suspends processing until status information is available for the specified child process, if the options argument is 0.
What is Wexitstatus?
This macro queries the child termination status provided by the wait and waitpid functions. If the WIFEXITED macro indicates that the child process exited normally, the WEXITSTATUS macro returns the exit code specified by the child process.
What is Wifstopped?
WIFSTOPPED, WIFSIGNALED, WIFEXITED, are macros that take an argument status , of type int, as returned by wait() , or wait3() , or wait4() . WIFSTOPPED evaluates to true (1) when the process for which the wait() call was made is stopped, or to false (0) otherwise.
What is Wifexited?
WIFEXITED and WEXITSTATUS are two of the options which can be used to know the exit status of the child. WIFEXITED(status) : returns true if the child terminated normally. WEXITSTATUS(status) : returns the exit status of the child. This macro should be employed only if WIFEXITED returned true.
Why do we use Waitpid?
It’s used generally to wait until a specific process finishes (or otherwise changes state if you’re using special flags), based on its process ID (otherwise known as a pid ). It can also be used to wait for any of a group of child processes, either one from a specific process group or any child of the current process.
What does Wnohang do in Waitpid?
If status information is immediately available on an appropriate child process, waitpid() returns this information. Otherwise, waitpid() returns immediately with an error code indicating that the information was not available. In other words, WNOHANG checks child processes without causing the caller to be suspended.
What is the difference between wait and Waitpid function?
Difference between wait and waitpid(): Wait() is a blocking call whereas waipid() can be made non-blocking with WNOHANG option. Wait() waits for any child process but waitpid() waits for a specific child equal to pid.
What does Wifexited do?
What is a define bottle?
The Define Bottle is basically a water bottle with a fruit infused container, capable of making thousands of variations of Fruit Infused Water. Kostler first came up with this invention when he was only 13 years old while watching his mother make pitchers of fruit infused water the family regularly consumed at home.
What is the difference between wifsignaled and wtermsig?
The WIFSIGNALED macro is always successful. If the child process for which status was returned by the wait or waitpid function exited because it raised a signal that caused it to exit, the WIFSIGNALED macro evaluates to TRUE and the WTERMSIG macro can be used to determine which signal was raised by the child process.
How to make your own flavored water bottle?
Great idea to have two compartments water bottle, which is separated by a filter. The Fresh fruit goes on the bottom and water goes in another chamber and plain old water for drinking goes through it. The fruit-infused water passes through the filter, to make the drinking water flavored naturally.
How much does a define bottle cost?
Great chains like Whole Foods and David’s Teas have introduced the Define bottles at a retail price of $30, with a cost of $10 which is a great margin to have per unit. His discussion with a Chinese manufacturer can get the cost down to $5 per unit. There are 2,000 hits per day on the website, with a conversion rate of 0.5%.