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See full version: Wait System Call in C


Artlav
31.05.2021 22:03:14

If any process has more than one child processes, then after calling wait(), parent process has to be in wait state if no child terminates.
If only one child process is terminated, then return a wait() returns process ID of the terminated child process.
If more than one child processes are terminated than wait() reap any arbitrarily child and return a process ID of that child process.
When wait() returns they also define exit status (which tells our, a process why terminated) via pointer, If status are not NULL.
If any process has no child process then wait() returns immediately “-1”.
NOTE: “This codes does not run in simple IDE because of environmental problem so use terminal for run the code”
Examples: here


Cablesaurus
14.05.2021 13:30:35

more


imnichol
01.06.2021 7:48:55

here


gena
15.05.2021 9:21:21

more


benderamp
19.05.2021 12:52:57

more


wholesale
31.05.2021 22:03:14

I've done this on QNX4.5 that doesn't support threads or Boost by using select . You basically pass select STDIN as the file descriptor to use and select will return when a new line is entered. I've added a simplified example loop below. It's platform independent, at least for Unix like systems. Not sure about Windows though. here


tehlaser
14.05.2021 13:30:35

I would do this by creating separate a thread which calls normal blocking IO functions and pass it a callback function which it would call when it got input. Are you sure you need to do what you said you want to do? more


Naniscegine
01.06.2021 7:48:55

Ans: do console IO on a background thread and provide a means of communicating between threads. here


kiav
15.05.2021 9:21:21

What's the best/easiest way to do this? I have no problem using external libraries like boost, as long as they use a permissive license. more


Sarahb1966
19.05.2021 12:52:57

As for outputting information at the same time, what would happen if the user was in the middle of typing some input and you printed something? more


Zodar
13.06.2021 14:32:32

M ThIErrHandle: action is STOP_WP, skip rollback


Xaxo
20.05.2021 19:14:03

M RqQQueueRelease: Return queue <T14_U874_M0> in slot 34 more


juliahollis89
10.05.2021 18:52:28

M PfClearAllRec: statRecordAction = STAT_RECORD_ACTION_REJECT


buggednot
20.04.2021 11:27:21

I brought SAP down for enabling SAP*, but now it is not starting.


caveden
19.05.2021 6:43:58

C -->oci_break(con=0,Acon=-1,cb=): cancel of current SQL more


v-tim
10.05.2021 16:02:19

M ThWpSetCurrentSession: set WP's current session to NO SESSION (rq_cnt 0, last wp -1, last rq_id 0)


gkelly
04.05.2021 23:38:26

Workaround: There is no workaround.


bethel
20.06.2021 5:16:02

Conditions: Slow Proc Memory depletion is observed on 7600-ES+ cards when installed on a Cisco 7600 router that has DLFIoATM configured on a PA-A6-OC3 hosted on an enhanced Flexwan module.


Felix Gabrielov
05.05.2021 12:11:46

Conditions: This symptom occurs during MPLS Transport Profile (TP) and OAM GAL handling.