Dear All,
I'm trying to write multithreading TCP Daemon which executes external program when new network connection arrives on a socket.
After accept() I'm doing fork() for initiating of new child process, in which will be executed external program. After child creation I'm doing fork() again,... (3 Replies)
I need to write a shell script which would take 2 arguments pid , userid. Then it should kill all the child process under it. If a child process is not killed then it should wait for 1 minute and should kill.
can anybody give me the idea to write it? (0 Replies)
hi, i want to write a code for forking 3 4 child. n wants that every child process one of the account from global account list. i wrote a program for that, but problem is every child is processing every account in list. what can me done to avoid it.
attaching code with it
#include <stdio.h>... (2 Replies)
Hi all,
I m writing an application, where i need to fork multiple childs and those child should handle particular task given to them.
More descriptive.
For example, suppose i have 4 Network, each network has multiple nodes. Now on the basis of network child should be forked and these child... (8 Replies)
Hello Friends,
Hope you are doing well.
I just need a help in executing multiple processes.
I've written a shell script which calls another scritps. But the problem is there are too many processes to run, and each process takes about a min to finish its execution.
So, I want to just... (3 Replies)
Hello guys!
I had seen some posts at this forum talking about my problem, but maybe my scenario is a little different, and I want other solutions.
I saw users of this forums saying that the way to shared sockets is using UNIX Sockets, but this is the only way in my scenario?
My Scenario:... (4 Replies)
Hi folks, I am writing a simple program to understand how fork() and waitpid works, but it doesn't seem that is working like I wanted.
if(fork()==0){
//el hijo
pid1=getpid();
printf("\nSoy el hijo %d",pid1);
}else {
//el padre
if (fork()==0) {
//el hijo
pid2=getpid();... (2 Replies)
I'm attempting to write a daemon that will start, stop, and monitor processes across a network of servers, meaning that a daemon would start on each server, attempt to connect to siblings at regular intervals (if there are unconnected siblings), and start services as remote dependencies are... (3 Replies)
Hey guys,
I have to make a C program that simulates this command :
cat (files here) | sort > file.txt
So, I start and create a pipe. Then create the first child. This first child will execute the Cat through the pipe. Then create a second child that will execute sort, with input from... (4 Replies)
Discussion started by: Poppo
4 Replies
LEARN ABOUT HPUX
vfork
vfork(2) System Calls Manual vfork(2)NAME
vfork - spawn new process; share virtual memory
SYNOPSIS REMARKS
is a higher performance version of that is provided on some systems where a performance advantage can be attained.
If the calling process is multi-threaded, the newly created child process will only contain one thread. This one thread will be a copy of
the thread calling
differs from only in that the child process can share code and data with the calling process (parent process). This speeds cloning activ-
ity significantly at a risk to the integrity of the parent process if is misused.
The use of for any purpose except as a prelude to an immediate or is not supported. Any program that relies upon the differences between
and is not portable across HP-UX systems.
All HP-UX implementations must provide the entry but it is permissible for them to treat it identically to On some implementations the two
are not distinguished because the implementation is as efficient as possible. Other versions may do the same to avoid the overhead of sup-
porting two similar calls.
DESCRIPTION
can be used to create new processes without fully copying the address space of the old process. If a forked process is simply going to do
an (see exec(2)), the data space copied from the parent to the child by is not used. This is particularly inefficient in a paged environ-
ment, making particularly useful. Depending upon the size of the parent's data space, can give a significant performance improvement over
differs from in that the child borrows the parent's memory and thread of control until a call to or an exit (either by a call to or abnor-
mally (see exec(2) and exit(2)). The parent process is suspended while the child is using its resources.
returns 0 in the child's context and (later) the pid of the child in the parent's context.
can normally be used just like It does not work, however, to return while running in the child's context from the procedure which called
since the eventual return from would then return to a no longer existent stack frame.
The window begins at the call and ends when the child completes its call.
RETURN VALUE
Upon successful completion, returns a value of 0 to the child process and returns the process ID of the child process to the parent
process. Otherwise, a value of -1 is returned to the parent, no child process is created, and is set to indicate the error.
ERRORS
fails and no child process is created if any of the following conditions are encountered:
The system-wide limit on the total number of processes under execution
would be exceeded.
The system-imposed limit on the total number of processes under execution
by a single user would be exceeded.
DEPENDENCIES
Servers
Process times for the parent and child processes within the window may be inaccurate.
Parent and child processes share the same stack space within the window. If the size of the stack has been changed within this win-
dow by the child process (return from or call to a function, for example), it is likely that the parent and child processes will be
killed with signal or
In the window, a call to (see signal(2) that installs a catching function can affect handling of the signal by the parent. The par-
ent is not affected if the handling is being set to or or if is used (see sigaction(2)).
AUTHOR
was developed by the University of California, Berkeley.
SEE ALSO exec(2), exit(2), fork(2), sigaction(2), wait(2).
vfork(2)