Thank you! Got it. Regards, Sundar
On Wednesday, January 24, 2018 at 3:23:04 PM UTC-8, Matt Harden wrote: > > When the program exits, all goroutines die instantly. The doc is saying > that the program does not wait for any goroutine to complete except the > "main" goroutine (the one that invoked the function main at startup). If > you do want to wait for other goroutines to exit before exiting the > program, which is often something you do want, that can be done using > sync.WaitGroup or other synchronization tools like channels. In the case of > Tamas's goroutine, nothing in main waits for it, assuming the program isn't > sent an interrupt signal, so the goroutine never "completes". It does > "exit" though, because all goroutines are part of the program, and when the > program exits, it exits entirely. Any goroutine that was running as part of > the program isn't running anymore, and in fact doesn't even "exist" in any > meaningful sense anymore. > > You are correct that contexts can be used to inform goroutines when to > perform cleanup steps and/or exit cleanly, but if you want to ensure that > the cleanup actually completes, you need to wait for the goroutine to > finish before returning from main (or running os.Exit, log.Fatal, panicking > without recovering, etc.). Otherwise the goroutine may abruptly stop > running at any time as the program exits. > > I hope that helps to clarify the documentation for you. > > On Wed, Jan 24, 2018 at 11:03 PM Sundar Nadathur <ns1.s...@gmail.com > <javascript:>> wrote: > >> I am probably mis-understanding or missing something. The golang spec >> <https://golang.org/ref/spec#Program_execution> says: >> Program execution begins by initializing the main package and then >> invoking the function main. When that function invocation returns, the >> program exits. *It does not wait for other (non-main) goroutines to >> complete*. >> >> I gather that the context mechanism addresses this issue, by requiring >> every relevant go routine to get a context as a parameter and to check for >> ctx.Done channel. Since calling cancel() would send a message through that >> channel, every goroutine that is designed to listen on that channel would >> 'get the message' and can do their own cleanup/exit. >> >> However, this specific goroutine does not receive the context. The golang >> spec seems to say that it is not guaranteed to exit when the app dies or >> exits. Please clarify. >> >> Regards, >> Sundar >> >> >> On Wednesday, January 24, 2018 at 12:05:35 PM UTC-8, Tamás Gulácsi wrote: >>> >>> if the main goroutine exits, all other goroutines exit, too. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "golang-nuts" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to golang-nuts...@googlegroups.com <javascript:>. >> For more options, visit https://groups.google.com/d/optout. >> > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
