What does the system call "dup" do?
What is the difference between dup and dup2
I have a fair idea of what it does but I am confused when its coming down to the exact details...
Please help me!:confused: (2 Replies)
open, creat, read, write, lseek and close
Are they all primitive?
:confused:
*Another Question: is there a different between a system call, and an i/o system call? (2 Replies)
Hi,
I'm new to UNIX system calls. Can someone share your knowledge as to how exactly system calls should be executed?
Can they be typed like commands such as mkdir on the terminal itself? Also, are there any websites which will show me an example of the output to expect when a system call like... (1 Reply)
Hello,
how would i be able to call ps in C programming?
thanks,
---------- Post updated at 01:39 AM ---------- Previous update was at 01:31 AM ----------
here's the complete system call, ps -o pid -p %d, getpit() (2 Replies)
All,
Kindly let me know command which is used to trace the system calls on HP - UX server when an executable is run.
On Solaris we have TRUSS which does the need. On HP UX we have TUSC command which is a third party software. Currently this is not installed on my HP Server. If there... (3 Replies)
Discussion started by: helper
3 Replies
LEARN ABOUT DEBIAN
io::async::pid
IO::Async::PID(3pm) User Contributed Perl Documentation IO::Async::PID(3pm)NAME
"IO::Async::PID" - event callback on exit of a child process
SYNOPSIS
use IO::Async::PID;
use POSIX qw( WEXITSTATUS );
use IO::Async::Loop;
my $loop = IO::Async::Loop->new;
my $kid = $loop->fork(
code => sub {
print "Child sleeping..
";
sleep 10;
print "Child exiting
";
return 20;
},
);
print "Child process $kid started
";
my $pid = IO::Async::PID->new(
pid => $kid,
on_exit => sub {
my ( $self, $exitcode ) = @_;
printf "Child process %d exited with status %d
",
$self->pid, WEXITSTATUS($exitcode);
},
);
$loop->add( $pid );
$loop->run;
DESCRIPTION
This subclass of IO::Async::Notifier invokes its callback when a process exits.
For most use cases, a IO::Async::Process object provides more control of setting up the process, connecting filehandles to it, sending data
to and receiving data from it.
EVENTS
The following events are invoked, either using subclass methods or CODE references in parameters:
on_exit $exitcode
Invoked when the watched process exits.
PARAMETERS
The following named parameters may be passed to "new" or "configure":
pid => INT
The process ID to watch. Must be given before the object has been added to the containing "IO::Async::Loop" object.
on_exit => CODE
CODE reference for the "on_exit" event.
Once the "on_exit" continuation has been invoked, the "IO::Async::PID" object is removed from the containing "IO::Async::Loop" object.
METHODS
$process_id = $pid->pid
Returns the underlying process ID
$pid->kill( $signal )
Sends a signal to the process
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>
perl v5.14.2 2012-10-24 IO::Async::PID(3pm)