Hey all. I recently ported a multithreaded program from WinNT to LINUX using pthreads. Everything works fine, except that it turns out the drivers for the hardware I'm working with aren't thread safe. So, now I have to find a way to make this multi-process instead of multi-threaded.
I just... (1 Reply)
I need a quick script that will serve as a sort of "real time monitor" for watching some log files. I am using Bourne shell in HP-UX 10.20. I have basically created a script that never ends, unless of course I manually terminate it. Here's the script (it's called qhistory):
clear
echo "REAL... (3 Replies)
hello,
Every time i use fork() in the for loop, my college network(which i work in) either gets slow or hangs up.Can any 1 explain why it is so?
Of course there is no use of doing it though. But still i want to clear my doubt.
Thanks (2 Replies)
I have a parent that is passing data to child A and then child A has to process it and pass to child B. I am able to pass the data to child A but am not able to pass it to child B. Child B seems to only be receiving the last data instead of the whole data.
I saw one example in a book but it uses... (1 Reply)
hai,
i am doing my masters degree in computers.please any one tell me about
fork(),semaphores,mutex,messaging queues,messaging using pipes ,and msgget(),msgrecv() funtions
in ipc programming .
i have exam on that i have a book but in that they not given clearly.
hope u will
... (2 Replies)
Hi! I'm trying to write this program: in my intentions it should get a message and send it to a second process (pid_upost), then to a third process (pid1, pid2, pid3, depending on the choice made when a new message is inserted). This program should write the message in a file (message1, message2 or... (1 Reply)
I was asked to look into a problem with a Sun Netra 440 in another department. On the server in question, the relevant 'uname -a' information is, "SunOS host1 5.9 Generic_118558-16 sun4u sparc SUNW,Netra-440". That information aside, while the other admin is logged into the ALOM, these errors are... (0 Replies)
I am trying to ping through a list of devices in parallel.
When the code below is executed, I enter a infinite loop.
I want to used the number of lines in the file as my boundry.
I am a perl rookie and just cant see whats wrong.
would appreciate help ...
use Net::Ping;
#
$filename... (0 Replies)
Hello people.
I'm trying to do something like a search engine.
Server runs in the background by using ./server & which has data from a textfile stored in an array.
Client then runs by using ./client
It will then prompt "Search for:"
For example, if I searched for Products called Instant... (0 Replies)
Hi Experts,
Need your help for checking te interprocess communications settings on HP-UX box.
Using ipcs command I am able to view Message queue,semapohores etc, but from that output I m not able to understand how to determine if there is any issue with ipc settings and how to resolve that? (1 Reply)
Discussion started by: sai_2507
1 Replies
LEARN ABOUT ULTRIX
fork
fork(2) System Calls Manual fork(2)Name
fork - create a new process
Syntax
#include <sys/types.h>
#include <unistd.h>
pid = fork()
pid_t pid;
Description
The system call causes creation of a new process. The new process (child process) is an exact copy of the calling process except for the
following:
o The child process has a unique process ID.
o The child process has a different parent process ID (that is, the process ID of the parent process).
o The child process has its own copy of the parent's descriptors. These descriptors reference the same underlying objects, so that, for
instance, file pointers in file objects are shared between the child and the parent, so that a on a descriptor in the child process
can affect a subsequent read or write by the parent. This descriptor copying is also used by the shell to establish standard input
and output for newly created processes as well as to set up pipes.
o The child processes resource utilizations are set to 0. For further information, see
Return Values
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 process, no child process is created, and the global variable errno is set to
indicate the error.
Diagnostics
The system call fails and no child process are created under the following conditions:
[EAGAIN] The system-imposed limit {PROC_MAX} on the total number of processes under execution would be exceeded.
[EAGAIN] The system-imposed limit {CHILD_MAX} on the total number of processes under execution by a single user would be exceeded.
[ENOMEM] There is insufficient swap space for the new process.
See Alsoexecve(2), wait(2)fork(2)