waitpid Questions
11
Solved
3
Solved
If I use a combination to kill a child process in batch and wait for it's termination, I use
kill $PID
wait $PID
If the process exists immediately, the wait will fail, since the pid is not runni...
2
Hello I am new to learning about system calls. I am currently learning about fork() and wait() system calls. I know that fork() creates a new child process. What confuses me is the wait() call.
Th...
Echolocation asked 29/9, 2020 at 6:51
2
Solved
I have just had a lecture that sums reaping as:
Reaping
Performed by parent on terminated child (using wait or waitpid)
Parent is given exit status information
Kernel then deletes zombie child p...
Nepotism asked 15/11, 2019 at 23:8
3
Solved
I know that waitpid() is used to wait for a process to finish, but how would one use it exactly?
Here what I want to do is, create two children and wait for the first child to finish, then kill th...
Matthieu asked 21/1, 2014 at 3:53
1
Solved
I want to implement yes | head -n 1 in Rust, properly
connecting pipes and checking exit statuses: i.e., I want to be able to
determine that yes exits due to SIGPIPE and that head completes
normall...
3
Solved
If I do this in a bash script:
sleep 10 &
sleep_pid=$!
some_command &
wait -n
cmd_pid=$!
if kill -0 $sleep_pid 2> /dev/null; then
# all ok
kill $sleep_pid
else
# some_command hung
...
3
I need to catch the returned value of a child process..
The problem is: with using the waitpid() function I can catch only 8 bits of the returned value
WEXITSTATUS(wstatus)
returns the exit st...
Manhattan asked 22/6, 2018 at 7:23
2
Solved
Consider this trivial example of fork()ing then waiting for a child to die in Perl:
#!/usr/bin/perl
use strict;
use warnings;
if (fork() == 0) {
exit(1);
}
waitpid(-1,0);
print $?;
Running ...
2
I was going through the documentation of the system call wait4() and in its man page it is written
These functions are obsolete; use waitpid(2) or waitid(2) in new programs.
So, I went through...
Byte asked 10/2, 2016 at 13:18
5
Solved
I'm trying to return an integer value from a child process.
However, if I use exit(1) I get 256 as the output from wait(). Using exit(-1) gives 65280.
Is there a way I can get the actual int value ...
2
Solved
I am a bit confused. As I understand, waitpid with a pid of -1 means that I wait for all child's to finish but if I add an option to the waitpid of WNOHANG, that options says to exit immediately if...
1
Context is this Redis issue. We have a wait3() call that waits for the AOF rewriting child to create the new AOF version on disk. When the child is done, the parent is notified via wait3() in order...
Xerophagy asked 30/11, 2015 at 8:46
1
Solved
I am starting a process using execv and letting it write to a file. I start a thread simultaneously that monitors the file so that it's size does not exceed a certain limit using stat.st_size. Now,...
1
Solved
In the below script I am trying to figure out how waitpid works, but it doesn't wait for ssh process to exit. done is printed right away and not after the ssh process exists.
Question
How to I ma...
2
Solved
The following code runs 2 children, who will wait for 10 seconds and terminate. The parent is sitting in a loop, waiting for the children to terminate:
#!/usr/bin/perl
use strict;
use warnings;
u...
Florentinoflorenza asked 7/6, 2013 at 9:14
2
Solved
I've got a program which generates a random number, n, then loops n times.
On each iteration, it randomizes the value of sleeptime, and calls fork. The child process sleeps for sleeptime seconds, ...
2
Solved
I am trying to mimic the bash feature of running process in the background if "&" is found at the end of the command. I have the following function...and I don't think it's doing what I want it...
4
Solved
I have a script that spawns a set of children. The parent must wait for each of the children to finish.
My script performs similar to the following perl script:
#! /usr/bin/perl
use strict;
use w...
Wistrup asked 6/6, 2012 at 23:5
1
Solved
I am running a multiprogrammed workload (based on SPEC CPU2006 benchmarks) on a POWER7 system using SUSE SLES 11.
Sometimes, each application in the workload consumes a significant amount of memory...
Jesusa asked 24/8, 2011 at 19:13
3
Solved
If I fork a child process, and the child process exits before the parent calls waitpid, then is the exit status information that is set by waitpid still valid? If so, when does it become not valid;...
1
Solved
I'm trying to figure out what the pid is of a process that sent the SIGCHLD signal, and I want to do this in a signal handler I created for SIGCHLD. How would I do this? I'm trying:
int pid = wait...
3
Solved
I'm testing code that is designed to detect when a child process has segfaulted. Imagine my surprised when this code does not always segfault:
#include <stdio.h>
int main() {
char *p = (ch...
Multimillionaire asked 14/11, 2009 at 19:35
4
Solved
I'm playing with waitpid() and signal() and I'm looking for reliable test cases for returning WIFSIGNALED(status) = WIFSTOPPED(status) = WIFCONTINUED (status) = true but can't find any...
Care to ...
1
© 2022 - 2024 — McMap. All rights reserved.